PHP TUTORIAL PHP is a powerful server-side scripting language for creating dynamic and interactive websites.PHP is the widely-used, free, and efficient alternative to competitors such as Microsoft's ASP. PHP is perfectly suited for Web development and can be embedded directly into the HTML code.The PHP syntax is very similar to Perl and C. PHP is often used together with Apache (web server) on various operating systems. It also supports ISAPI and can be used with Microsoft's IIS on Windows.PHP is a server-side scripting language What You Should Already Know Before you continue you should have a basic understanding of the following: HTML Some scripting knowledge What is PHP? PHP stands for PHP: Hypertext Preprocessor PHP is a server-side scripting language, like ASP PHP scripts are executed on the server PHP supports many databases (MySQL, Informix, Oracle, Sybase, Solid, PostgreSQL, Generic ODBC, etc.) PHP is an open source software PHP is free to download and use What is a PHP File? PHP files can contain text, HTML tags and scripts PHP files are returned to the browser as plain HTML PHP files have a file extension of ".php", ".php3", or ".phtml" What is MySQL? MySQL is a database server MySQL is ideal for both small and large applications MySQL supports standard SQL MySQL compiles on a number of platforms MySQL is free to download and use PHP + MySQL PHP combined with MySQL are cross-platform (you can develop in Windows and serve on a Unix platform) Why PHP? PHP runs on different platforms (Windows, Linux, Unix, etc.) PHP is compatible with almost all servers used today (Apache, IIS, etc.) PHP is FREE to download from the official PHP resource: www.php.net PHP is easy to learn and runs efficiently on the server side Where to Start? To get access to a web server with PHP support, you can: Install Apache (or IIS) on your own server, install PHP, and MySQL Or find a web hosting plan with PHP and MySQL support PHP Installation What do You Need? If your server supports PHP you don't need to do anything. Just create some .php files in your web directory, and the server will parse them for you. Because it is free, most web hosts offer PHP support. However, if your server does not support PHP, you must install PHP. Here is a link to a good tutorial from PHP.net on how to install PHP5: http://www.php.net/manual/en/install.php Download PHP Download PHP for free here: http://www.php.net/downloads.php Download MySQL Database Download MySQL for free here: http://www.mysql.com/downloads/index.html Download Apache Server Download Apache for free here: http://httpd.apache.org/download.cgi PHP Syntax PHP code is executed on the server, and the plain HTML result is sent to the browser.

Basic PHP Syntax

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A PHP scripting block always starts with . A PHP scripting block can be placed anywhere in the document. On servers with shorthand support enabled you can start a scripting block with . For maximum compatibility, we recommend that you use the standard form ( A PHP file normally contains HTML tags, just like an HTML file, and some PHP scripting code. Below, we have an example of a simple PHP script which sends the text "Hello World" to the browser: Each code line in PHP must end with a semicolon. The semicolon is a separator and is used to distinguish one set of instructions from another. There are two basic statements to output text with PHP: echo and print. In the example above we have used the echo statement to output the text "Hello World". Note: The file must have the .php extension. If the file has a .html extension, the PHP code will not be executed. Comments in PHP In PHP, we use // to make a single-line comment or /* and */ to make a large comment block. PHP Variables Variables are used for storing values, such as numbers, strings or function results, so that they can be used many times in a script. Variables in PHP Variables are used for storing a values, like text strings, numbers or arrays. When a variable is set it can be used over and over again in your script All variables in PHP start with a $ sign symbol. The correct way of setting a variable in PHP: $var_name = value; New PHP programmers often forget the $ sign at the beginning of the variable. In that case it will not work. Let's try creating a variable with a string, and a variable with a number:

PHP is a Loosely Typed Language In PHP a variable does not need to be declared before being set. In the example above, you see that you do not have to tell PHP which data type the variable is.

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PHP automatically converts the variable to the correct data type, depending on how they are set. In a strongly typed programming language, you have to declare (define) the type and name of the variable before using it. In PHP the variable is declared automatically when you use it. Variable Naming Rules A variable name must start with a letter or an underscore "_" A variable name can only contain alpha-numeric characters and underscores (a-z, A-Z, 0-9, and _ ) A variable name should not contain spaces. If a variable name is more than one word, it should be separated with underscore ($my_string), or with capitalization ($myString) A string variable is used to store and manipulate a piece of text. Strings in PHP String variables are used for values that contains character strings. In this tutorial we are going to look at some of the most common functions and operators used to manipulate strings in PHP. After we create a string we can manipulate it. A string can be used directly in a function or it can be stored in a variable. Below, the PHP script assigns the string "Hello World" to a string variable called $txt: The output of the code above will be: Hello World Now, lets try to use some different functions and operators to manipulate our string. The Concatenation Operator There is only one string operator in PHP. The concatenation operator (.) is used to put two string values together. To concatenate two variables together, use the dot (.) operator: The output of the code above will be: Hello World 1234 If we look at the code above you see that we used the concatenation operator two times. This is because we had to insert a third string. Between the two string variables we added a string with a single character, an empty space, to separate the two variables. Using the strlen() function The strlen() function is used to find the length of a string. Let's find the length of our string "Hello world!": The output of the code above will be: 12 The length of a string is often used in loops or other functions, when it is important to know when the string ends. (i.e. in a loop, we would want to stop the loop after the last character in the string) Using the strpos() function The strpos() function is used to search for a string or character within a string. If a match is found in the string, this function will return the position of the first match. If no match is found, it will return FALSE.

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Let's see if we can find the string "world" in our string: The output of the code above will be: 6 As you see the position of the string "world" in our string is position 6. The reason that it is 6, and not 7, is that the first position in the string is 0, and not 1.

PHP String Introduction The string functions allow you to manipulate strings. Installation The string functions are part of the PHP core. There is no installation needed to use these functions. PHP String Functions PHP: indicates the earliest version of PHP that supports the function. Function Description PHP addcslashes() Returns a string with backslashes in front of the specified 4 characters addslashes() Returns a string with backslashes in front of predefined 3 characters bin2hex() Converts a string of ASCII characters to hexadecimal values 3 chop() Alias of rtrim() 3 chr() Returns a character from a specified ASCII value 3 chunk_split() Splits a string into a series of smaller parts 3 convert_cyr_string() Converts a string from one Cyrillic character-set to another 3 convert_uudecode() Decodes a uuencoded string 5 convert_uuencode() Encodes a string using the uuencode algorithm 5 count_chars() Returns how many times an ASCII character occurs within a 4 string and returns the information crc32() Calculates a 32-bit CRC for a string 4 crypt() One-way string encryption (hashing) 3 echo() Outputs strings 3 explode() Breaks a string into an array 3 fprintf() Writes a formatted string to a specified output stream 5 get_html_translation_table() Returns the translation table used by htmlspecialchars() and 4 htmlentities() hebrev() Converts Hebrew text to visual text 3 hebrevc() Converts Hebrew text to visual text and new lines (\n) into
html_entity_decode() Converts HTML entities to characters 4 htmlentities() Converts characters to HTML entities 3 htmlspecialchars_decode() Converts some predefined HTML entities to characters 5 htmlspecialchars() Converts some predefined characters to HTML entities 3 implode() Returns a string from the elements of an array 3 join() Alias of implode() 3 levenshtein() Returns the Levenshtein distance between two strings 3 localeconv() Returns locale numeric and monetary formatting information 4 ltrim() Strips whitespace from the left side of a string 3 md5() Calculates the MD5 hash of a string 3 md5_file() Calculates the MD5 hash of a file 4 metaphone() Calculates the metaphone key of a string 4

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money_format() nl_langinfo() nl2br() number_format() ord() parse_str() print() printf() quoted_printable_decode() quotemeta() rtrim() setlocale() sha1() sha1_file() similar_text() soundex() sprintf() sscanf() str_ireplace() str_pad() str_repeat() str_replace() str_rot13() str_shuffle() str_split() str_word_count() strcasecmp() strchr() strcmp() strcoll() strcspn() strip_tags() stripcslashes() stripslashes() stripos() stristr() strlen() strnatcasecmp() strnatcmp() strncasecmp() strncmp() strpbrk() strpos() strrchr()

Returns a string formatted as a currency string 4 Returns specific local information 4 Inserts HTML line breaks in front of each newline in a string 3 Formats a number with grouped thousands 3 Returns the ASCII value of the first character of a string 3 Parses a query string into variables 3 Outputs a string 3 Outputs a formatted string 3 Decodes a quoted-printable string 3 Quotes meta characters 3 Strips whitespace from the right side of a string 3 Sets locale information 3 Calculates the SHA-1 hash of a string 4 Calculates the SHA-1 hash of a file 4 Calculates the similarity between two strings 3 Calculates the soundex key of a string 3 Writes a formatted string to a variable 3 Parses input from a string according to a format 4 Replaces some characters in a string (case-insensitive) 5 Pads a string to a new length 4 Repeats a string a specified number of times 4 Replaces some characters in a string (case-sensitive) 3 Performs the ROT13 encoding on a string 4 Randomly shuffles all characters in a string 4 Splits a string into an array 5 Count the number of words in a string 4 Compares two strings (case-insensitive) 3 Finds the first occurrence of a string inside another string 3 (alias of strstr()) Compares two strings (case-sensitive) 3 Locale based string comparison 4 Returns the number of characters found in a string before any 3 part of some specified characters are found Strips HTML and PHP tags from a string 3 Unquotes a string quoted with addcslashes() 4 Unquotes a string quoted with addslashes() 3 Returns the position of the first occurrence of a string inside 5 another string (case-insensitive) Finds the first occurrence of a string inside another string 3 (case-insensitive) Returns the length of a string 3 Compares two strings using a "natural order" algorithm (case- 4 insensitive) Compares two strings using a "natural order" algorithm (case- 4 sensitive) String comparison of the first n characters (case-insensitive) 4 String comparison of the first n characters (case-sensitive) 4 Searches a string for any of a set of characters 5 Returns the position of the first occurrence of a string inside 3 another string (case-sensitive) Finds the last occurrence of a string inside another string 3

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strrev() strripos() strrpos() strspn() strstr() strtok() strtolower() strtoupper() strtr() substr() substr_compare() substr_count() substr_replace() trim() ucfirst() ucwords() vfprintf() vprintf() vsprintf() wordwrap()

Reverses a string Finds the position of the last occurrence of a string inside another string (case-insensitive) Finds the position of the last occurrence of a string inside another string (case-sensitive) Returns the number of characters found in a string that contains only characters from a specified charlist Finds the first occurrence of a string inside another string (case-sensitive) Splits a string into smaller strings Converts a string to lowercase letters Converts a string to uppercase letters Translates certain characters in a string Returns a part of a string Compares two strings from a specified start position (binary safe and optionally case-sensitive) Counts the number of times a substring occurs in a string Replaces a part of a string with another string Strips whitespace from both sides of a string Converts the first character of a string to uppercase Converts the first character of each word in a string to uppercase Writes a formatted string to a specified output stream Outputs a formatted string Writes a formatted string to a variable Wraps a string to a given number of characters

3 5 3 3 3 3 3 3 3 3 5 4 4 3 3 3 5 4 4 4

PHP String Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description PHP CRYPT_SALT_LENGTH Contains the length of the default encryption method for the system. For standard DES encryption, the length is 2 CRYPT_STD_DES Set to 1 if the standard DES-based encryption with a 2 character salt is supported, 0 otherwise CRYPT_EXT_DES Set to 1 if the extended DES-based encryption with a 9 character salt is supported, 0 otherwise CRYPT_MD5 Set to 1 if the MD5 encryption with a 12 character salt starting with $1$ is supported, 0 otherwise CRYPT_BLOWFISH Set to 1 if the Blowfish encryption with a 16 character salt starting with $2$ or $2a$ is supported, 0 otherwise0 HTML_SPECIALCHARS HTML_ENTITIES ENT_COMPAT ENT_QUOTES ENT_NOQUOTES CHAR_MAX LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY

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LC_ALL LC_MESSAGES STR_PAD_LEFT STR_PAD_RIGHT STR_PAD_BOTH PHP XML Parser Introduction The XML functions lets you parse, but not validate, XML documents. XML is a data format for standardized structured document exchange. More information on XML can be found in our XML Tutorial. This extension uses the Expat XML parser. Expat is an event-based parser, it views an XML document as a series of events. When an event occurs, it calls a specified function to handle it. Expat is a non-validating parser, and ignores any DTDs linked to a document. However, if the document is not well formed it will end with an error message. Because it is an event-based, non validating parser, Expat is fast and well suited for web applications. The XML parser functions lets you create XML parsers and define handlers for XML events. Installation The XML functions are part of the PHP core. There is no installation needed to use these functions. PHP XML Parser Functions PHP: indicates the earliest version of PHP that supports the function. Function Description PHP utf8_decode() Decodes an UTF-8 string to ISO-8859-1 3 utf8_encode() Encodes an ISO-8859-1 string to UTF-8 3 xml_error_string() Gets an error string from the XML parser 3 xml_get_current_byte_index() Gets the current byte index from the XML 3 parser xml_get_current_column_number() Gets the current column number from the 3 XML parser xml_get_current_line_number() Gets the current line number from the XML 3 parser xml_get_error_code() Gets an error code from the XML parser 3 xml_parse() Parses an XML document 3 xml_parse_into_struct() Parse XML data into an array 3 xml_parser_create_ns() Create an XML parser with namespace 4 support xml_parser_create() Create an XML parser 3 xml_parser_free() Free an XML parser 3 xml_parser_get_option() Get options from an XML parser 3 xml_parser_set_option() Set options in an XML parser 3 xml_set_character_data_handler() Set handler function for character data 3 xml_set_default_handler() Set default handler function 3 xml_set_element_handler() Set handler function for start and end element 3 of elements xml_set_end_namespace_decl_handler() Set handler function for the end of namespace 4 declarations xml_set_external_entity_ref_handler() Set handler function for external entities 3 xml_set_notation_decl_handler() Set handler function for notation declarations 3 xml_set_object() Use XML Parser within an object 4 xml_set_processing_instruction_handler() Set handler function for processing instruction 3 xml_set_start_namespace_decl_handler() Set handler function for the start of 4 namespace declarations

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xml_set_unparsed_entity_decl_handler()

Set handler function for unparsed entity declarations

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PHP XML Parser Constants Constant XML_ERROR_NONE (integer) XML_ERROR_NO_MEMORY (integer) XML_ERROR_SYNTAX (integer) XML_ERROR_NO_ELEMENTS (integer) XML_ERROR_INVALID_TOKEN (integer) XML_ERROR_UNCLOSED_TOKEN (integer) XML_ERROR_PARTIAL_CHAR (integer) XML_ERROR_TAG_MISMATCH (integer) XML_ERROR_DUPLICATE_ATTRIBUTE (integer) XML_ERROR_JUNK_AFTER_DOC_ELEMENT (integer) XML_ERROR_PARAM_ENTITY_REF (integer) XML_ERROR_UNDEFINED_ENTITY (integer) XML_ERROR_RECURSIVE_ENTITY_REF (integer) XML_ERROR_ASYNC_ENTITY (integer) XML_ERROR_BAD_CHAR_REF (integer) XML_ERROR_BINARY_ENTITY_REF (integer) XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF (integer) XML_ERROR_MISPLACED_XML_PI (integer) XML_ERROR_UNKNOWN_ENCODING (integer) XML_ERROR_INCORRECT_ENCODING (integer) XML_ERROR_UNCLOSED_CDATA_SECTION (integer) XML_ERROR_EXTERNAL_ENTITY_HANDLING (integer) XML_OPTION_CASE_FOLDING (integer) XML_OPTION_TARGET_ENCODING (integer) XML_OPTION_SKIP_TAGSTART (integer) XML_OPTION_SKIP_WHITE (integer)

PHP Zip File Introduction The Zip files functions allows you to read ZIP files. Installation For the Zip file functions to work on your server, these libraries must be installed: The ZZIPlib library by Guido Draheim: Download the ZZIPlib library The Zip PELC extension: Download the Zip PELC extension Installation on Linux Systems PHP 5+: Zip functions and the Zip library is not enabled by default and must be downloaded from the links above. Use the --with-zip=DIR configure option to include Zip support. Installation on Windows Systems PHP 5+: Zip functions is not enabled by default, so the php_zip.dll and the ZZIPlib library must be downloaded from the link above. php_zip.dll must be enabled inside of php.ini. To enable any PHP extension, the PHP extension_dir setting (in the php.ini file) should be set to the directory where the PHP extensions are located. An example extension_dir value is c:\php\ext. PHP Zip File Functions PHP: indicates the earliest version of PHP that supports the function. Function Description zip_close() Closes a ZIP file

PHP 4

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zip_entry_close() zip_entry_compressedsize() zip_entry_compressionmethod() zip_entry_filesize() zip_entry_name() zip_entry_open() zip_entry_read() zip_open() zip_read()

Closes an entry in the ZIP file Returns the compressed size of an entry in the ZIP file Returns the compression method of an entry in the ZIP file Returns the actual file size of an entry in the ZIP file Returns the name of an entry in the ZIP file Opens an entry in the ZIP file for reading Reads from an open entry in the ZIP file Opens a ZIP file Reads the next entry in a ZIP file

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PHP Zip File Constants NONE You can test your PHP skills with W3Schools' Quiz. Operators are used to operate on values. PHP Operators This section lists the different operators used in PHP. Arithmetic Operators Operator Description + Addition -

Subtraction

*

Multiplication

/

Division

%

Modulus (division remainder)

++

Increment

--

Decrement

Example x=2 x+2 x=2 5-x x=4 x*5 15/5 5/2 5%2 10%8 10%2 x=5 x++ x=5 x--

Assignment Operators Operator Example = x=y += x+=y -= x-=y *= x*=y /= x/=y .= x.=y %= x%=y

Is The Same As x=y x=x+y x=x-y x=x*y x=x/y x=x.y x=x%y

Comparison Operators Operator Description == is equal to != is not equal > is greater than < is less than >= is greater than or equal to

Example 5==8 returns false 5!=8 returns true 5>8 returns false 5<8 returns true 5>=8 returns false

Result 4 3 20 3 2.5 1 2 0 x=6 x=4

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<=

is less than or equal to

Logical Operators Operator Description && and

||

or

!

not

5<=8 returns true

Example x=6 y=3 (x < 10 && y > 1) returns true x=6 y=3 (x==5 || y==5) returns false x=6 y=3 !(x==y) returns true

PHP If...Else Statements The if, elseif and else statements in PHP are used to perform different actions based on different conditions. Conditional Statements Very often when you write code, you want to perform different actions for different decisions. You can use conditional statements in your code to do this. if...else statement - use this statement if you want to execute a set of code when a condition is true and another if the condition is not true elseif statement - is used with the if...else statement to execute a set of code if one of several condition are true The If...Else Statement If you want to execute some code if a condition is true and another code if a condition is false, use the if....else statement. Syntax if (condition) code to be executed if condition is true; else code to be executed if condition is false; Example The following example will output "Have a nice weekend!" if the current day is Friday, otherwise it will output "Have a nice day!": If more than one line should be executed if a condition is true/false, the lines should be enclosed within curly braces: "; echo "Have a nice weekend!";

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echo "See you on Monday!"; } ?>

The ElseIf Statement If you want to execute some code if one of several conditions are true use the elseif statement Syntax if (condition) code to be executed if condition is true; elseif (condition) code to be executed if condition is true; else code to be executed if condition is false; Example The following example will output "Have a nice weekend!" if the current day is Friday, and "Have a nice Sunday!" if the current day is Sunday. Otherwise it will output "Have a nice day!": PHP Switch Statement The Switch statement in PHP is used to perform one of several different actions based on one of several different conditions. The Switch Statement If you want to select one of many blocks of code to be executed, use the Switch statement. The switch statement is used to avoid long blocks of if..elseif..else code. Syntax switch (expression) { case label1: code to be executed if expression = label1; break; case label2: code to be executed if expression = label2; break; default: code to be executed if expression is different from both label1 and label2; } Example This is how it works: A single expression (most often a variable) is evaluated once The value of the expression is compared with the values for each case in the structure

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If there is a match, the code associated with that case is executed After a code is executed, break is used to stop the code from running into the next case The default statement is used if none of the cases are true

PHP Arrays An array can store one or more values in a single variable name. What is an array? When working with PHP, sooner or later, you might want to create many similar variables. Instead of having many similar variables, you can store the data as elements in an array. Each element in the array has its own ID so that it can be easily accessed. There are three different kind of arrays: Numeric array - An array with a numeric ID key Associative array - An array where each ID key is associated with a value Multidimensional array - An array containing one or more arrays Numeric Arrays A numeric array stores each element with a numeric ID key. There are different ways to create a numeric array. Example 1 In this example the ID key is automatically assigned: $names = array("Peter","Quagmire","Joe"); Example 2 In this example we assign the ID key manually: $names[0] = "Peter"; $names[1] = "Quagmire"; $names[2] = "Joe"; The ID keys can be used in a script: The code above will output: Quagmire and Joe are Peter's neighbors

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Associative Arrays An associative array, each ID key is associated with a value. When storing data about specific named values, a numerical array is not always the best way to do it. With associative arrays we can use the values as keys and assign values to them. Example 1 In this example we use an array to assign ages to the different persons: $ages = array("Peter"=>32, "Quagmire"=>30, "Joe"=>34); Example 2 This example is the same as example 1, but shows a different way of creating the array: $ages['Peter'] = "32"; $ages['Quagmire'] = "30"; $ages['Joe'] = "34"; The ID keys can be used in a script: The code above will output: Peter is 32 years old.

Multidimensional Arrays In a multidimensional array, each element in the main array can also be an array. And each element in the sub-array can be an array, and so on. Example In this example we create a multidimensional array, with automatically assigned ID keys: $families = array ( "Griffin"=>array ( "Peter", "Lois", "Megan" ), "Quagmire"=>array ( "Glenn" ), "Brown"=>array ( "Cleveland", "Loretta", "Junior" ) ); The array above would look like this if written to the output: Array ( [Griffin] => Array ( [0] => Peter [1] => Lois [2] => Megan )

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[Quagmire] => Array ( [0] => Glenn ) [Brown] => Array ( [0] => Cleveland [1] => Loretta [2] => Junior ) ) Example 2 Lets try displaying a single value from the array above: echo "Is " . $families['Griffin'][2] . " a part of the Griffin family?"; The code above will output: Is Megan a part of the Griffin family? PHP Looping Looping statements in PHP are used to execute the same block of code a specified number of times. Looping Very often when you write code, you want the same block of code to run a number of times. You can use looping statements in your code to perform this. In PHP we have the following looping statements: while - loops through a block of code if and as long as a specified condition is true do...while - loops through a block of code once, and then repeats the loop as long as a special condition is true for - loops through a block of code a specified number of times foreach - loops through a block of code for each element in an array The while Statement The while statement will execute a block of code if and as long as a condition is true. Syntax while (condition) code to be executed; Example The following example demonstrates a loop that will continue to run as long as the variable i is less than, or equal to 5. i will increase by 1 each time the loop runs: "; $i++; } ?> The do...while Statement The do...while statement will execute a block of code at least once - it then will repeat the loop as long as a condition is true. Syntax do { code to be executed;

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} while (condition); Example The following example will increment the value of i at least once, and it will continue incrementing the variable i as long as it has a value of less than 5: "; } while ($i<5); ?>

The for Statement The for statement is the most advanced of the loops in PHP. In it's simplest form, the for statement is used when you know how many times you want to execute a statement or a list of statements. Syntax for (init; cond; incr) { code to be executed; } Parameters: init: Is mostly used to set a counter, but can be any code to be executed once at the beginning of the loop statement. cond: Is evaluated at beginning of each loop iteration. If the condition evaluates to TRUE, the loop continues and the code executes. If it evaluates to FALSE, the execution of the loop ends. incr: Is mostly used to increment a counter, but can be any code to be executed at the end of each loop. Note: Each of the parameters can be empty or have multiple expressions separated by commas. cond: All expressions separated by a comma are evaluated but the result is taken from the last part. This parameter being empty means the loop should be run indefinitely. This is useful when using a conditional break statement inside the loop for ending the loop. Example The following example prints the text "Hello World!" five times: "; } ?>

The foreach Statement The foreach statement is used to loop through arrays. For every loop, the value of the current array element is assigned to $value (and the array pointer is moved by one) - so on the next loop, you'll be looking at the next element. Syntax

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foreach (array as value) { code to be executed; } Example The following example demonstrates a loop that will print the values of the given array: "; } ?> PHP Functions The real power of PHP comes from its functions. In PHP - there are more than 700 built-in functions available. PHP Functions In this tutorial we will show you how to create your own functions. For a reference and examples of the built-in functions, please visit our PHP Reference. Create a PHP Function A function is a block of code that can be executed whenever we need it. Creating PHP functions: All functions start with the word "function()" Name the function - It should be possible to understand what the function does by its name. The name can start with a letter or underscore (not a number) Add a "{" - The function code starts after the opening curly brace Insert the function code Add a "}" - The function is finished by a closing curly brace Example A simple function that writes my name when it is called:

Use a PHP Function Now we will use the function in a PHP script:
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} echo "Hello world!
"; echo "My name is "; writeMyName(); echo ".
That's right, "; writeMyName(); echo " is my name."; ?> The output of the code above will be: Hello world! My name is Kai Jim Refsnes. That's right, Kai Jim Refsnes is my name.

PHP Functions - Adding parameters Our first function (writeMyName()) is a very simple function. It only writes a static string. To add more functionality to a function, we can add parameters. A parameter is just like a variable. You may have noticed the parentheses after the function name, like: writeMyName(). The parameters are specified inside the parentheses. Example 1 The following example will write different first names, but the same last name: "; } echo "My name is "; writeMyName("Kai Jim"); echo "My name is "; writeMyName("Hege"); echo "My name is "; writeMyName("Stale"); ?> The output of the code above will be: My name is Kai Jim Refsnes. My name is Hege Refsnes. My name is Stale Refsnes. Example 2 The following function has two parameters: "; } echo "My name is "; writeMyName("Kai Jim","."); echo "My name is "; writeMyName("Hege","!"); echo "My name is "; writeMyName("Ståle","..."); ?>

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The output of the code above will be: My name is Kai Jim Refsnes. My name is Hege Refsnes! My name is Ståle Refsnes...

PHP Functions - Return values Functions can also be used to return values. Example The output of the code above will be: 1 + 16 = 17

PHP Forms and User Input The PHP $_GET and $_POST variables are used to retrieve information from forms, like user input. PHP Form Handling The most important thing to notice when dealing with HTML forms and PHP is that any form element in an HTML page will automatically be available to your PHP scripts. Form example:

Name: Age:

The example HTML page above contains two input fields and a submit button. When the user fills in this form and click on the submit button, the form data is sent to the "welcome.php" file. The "welcome.php" file looks like this: Welcome .
You are years old. A sample output of the above script may be: Welcome John. You are 28 years old. The PHP $_GET and $_POST variables will be explained in the next chapters.

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Form Validation User input should be validated whenever possible. Client side validation is faster, and will reduce server load. However, any site that gets enough traffic to worry about server resources, may also need to worry about site security. You should always use server side validation if the form accesses a database. A good way to validate a form on the server is to post the form to itself, instead of jumping to a different page. The user will then get the error messages on the same page as the form. This makes it easier to discover the error. PHP $_GET The $_GET variable is used to collect values from a form with method="get". The $_GET Variable The $_GET variable is an array of variable names and values sent by the HTTP GET method. The $_GET variable is used to collect values from a form with method="get". Information sent from a form with the GET method is visible to everyone (it will be displayed in the browser's address bar) and it has limits on the amount of information to send (max. 100 characters). Example

Name: Age:

When the user clicks the "Submit" button, the URL sent could look something like this: http://www.w3schools.com/welcome.php?name=Peter&age=37 The "welcome.php" file can now use the $_GET variable to catch the form data (notice that the names of the form fields will automatically be the ID keys in the $_GET array): Welcome .
You are years old!

Why use $_GET? Note: When using the $_GET variable all variable names and values are displayed in the URL. So this method should not be used when sending passwords or other sensitive information! However, because the variables are displayed in the URL, it is possible to bookmark the page. This can be useful in some cases. Note: The HTTP GET method is not suitable on large variable values; the value cannot exceed 100 characters. The $_REQUEST Variable The PHP $_REQUEST variable contains the contents of both $_GET, $_POST, and $_COOKIE. The PHP $_REQUEST variable can be used to get the result from form data sent with both the GET and POST methods. Example Welcome .
You are years old! PHP $_POST The $_POST variable is used to collect values from a form with method="post". The $_POST Variable The $_POST variable is an array of variable names and values sent by the HTTP POST method. The $_POST variable is used to collect values from a form with method="post". Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send. Example

Enter your name: Enter your age:

19

When the user clicks the "Submit" button, the URL will not contain any form data, and will look something like this: http://www.w3schools.com/welcome.php The "welcome.php" file can now use the $_POST variable to catch the form data (notice that the names of the form fields will automatically be the ID keys in the $_POST array): Welcome .
You are years old!

Why use $_POST? Variables sent with HTTP POST are not shown in the URL Variables have no length limit However, because the variables are not displayed in the URL, it is not possible to bookmark the page. The $_REQUEST Variable The PHP $_REQUEST variable contains the contents of both $_GET, $_POST, and $_COOKIE. The PHP $_REQUEST variable can be used to get the result from form data sent with both the GET and POST methods. Example Welcome .
You are years old!

PHP Advanced PHP Date() The PHP date() function is used to format a time or a date. The PHP Date() Function The PHP date() function formats a timestamp to a more readable date and time. Syntax date(format,timestamp) Parameter format timestamp

Description Required. Specifies the format of the timestamp Optional. Specifies a timestamp. Default is the current date and time (as a timestamp)

PHP Date - What is a Timestamp? A timestamp is the number of seconds since January 1, 1970 at 00:00:00 GMT. This is also known as the Unix Timestamp. PHP Date - Format the Date The first parameter in the date() function specifies how to format the date/time. It uses letters to represent date and time formats. Here are some of the letters that can be used: d - The day of the month (01-31) m - The current month, as a number (01-12) Y - The current year in four digits An overview of all the letters that can be used in the format parameter, can be found in our PHP Date reference. Other characters, like"/", ".", or "-" can also be inserted between the letters to add additional formatting: "; echo date("Y.m.d"); echo "
";

20

echo date("Y-m-d"); ?> The output of the code above could be something like this: 2006/07/11 2006.07.11 2006-07-11

PHP Date - Adding a Timestamp The second parameter in the date() function specifies a timestamp. This parameter is optional. If you do not supply a timestamp, the current time will be used. In our next example we will use the mktime() function to create a timestamp for tomorrow. The mktime() function returns the Unix timestamp for a specified date. Syntax mktime(hour,minute,second,month,day,year,is_dst) To go one day in the future we simply add one to the day argument of mktime(): The output of the code above could be something like this: Tomorrow is 2006/07/12 PHP Date / Time Functions PHP Date / Time Introduction The date/time functions allow you to extract and format the date and time on the server. Note: These functions depend on the locale settings of the server! Installation The date/time functions are part of the PHP core. There is no installation needed to use these functions. Runtime Configuration The behavior of the date/time functions is affected by settings in php.ini. Date/Time configuration options: Name Default Description Changeable date.default_latitude "31.7667" Specifies the default latitude (available since PHP_INI_ALL PHP 5). This option is used by date_sunrise() and date_sunset() date.default_longitude "35.2333" Specifies the default longitude (available PHP_INI_ALL since PHP 5). This option is used by date_sunrise() and date_sunset() date.sunrise_zenith "90.83" Specifies the default sunrise zenith (available PHP_INI_ALL since PHP 5). This option is used by date_sunrise() and date_sunset() date.sunset_zenith "90.83" Specifies the default sunset zenith (available PHP_INI_ALL since PHP 5). This option is used by date_sunrise() and date_sunset() date.timezone "" Specifies the default timezone (available PHP_INI_ALL since PHP 5.1)

PHP Date / Time Functions PHP: indicates the earliest version of PHP that supports the function. Function Description checkdate() Validates a Gregorian date date_default_timezone_get() Returns the default time zone

PHP 3 5

21

date_default_timezone_set() date_sunrise() date_sunset() date() getdate() gettimeofday() gmdate() gmmktime() gmstrftime() idate() localtime() microtime() mktime() strftime() strptime() strtotime() time()

Sets the default time zone 5 Returns the time of sunrise for a given day / location 5 Returns the time of sunset for a given day / location 5 Formats a local time/date 3 Returns an array that contains date and time information for a 3 Unix timestamp Returns an array that contains current time information 3 Formats a GMT/UTC date/time 3 Returns the Unix timestamp for a GMT date 3 Formats a GMT/UTC time/date according to locale settings 3 Formats a local time/date as integer 5 Returns an array that contains the time components of a Unix 4 timestamp Returns the microseconds for the current time 3 Returns the Unix timestamp for a date 3 Formats a local time/date according to locale settings 3 Parses a time/date generated with strftime() 5 Parses an English textual date or time into a Unix timestamp 3 Returns the current time as a Unix timestamp 3

PHP Date / Time Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description PHP DATE_ATOM Atom (example: 2005-08-15T16:13:03+0000) DATE_COOKIE HTTP Cookies (example: Sun, 14 Aug 2005 16:13:03 UTC) DATE_ISO8601 ISO-8601 (example: 2005-08-14T16:13:03+0000) DATE_RFC822 RFC 822 (example: Sun, 14 Aug 2005 16:13:03 UTC) DATE_RFC850 RFC 850 (example: Sunday, 14-Aug-05 16:13:03 UTC) DATE_RFC1036 RFC 1036 (example: Sunday, 14-Aug-05 16:13:03 UTC) DATE_RFC1123 RFC 1123 (example: Sun, 14 Aug 2005 16:13:03 UTC) DATE_RFC2822 RFC 2822 (Sun, 14 Aug 2005 16:13:03 +0000) DATE_RSS RSS (Sun, 14 Aug 2005 16:13:03 UTC) DATE_W3C World Wide Web Consortium (example: 2005-0814T16:13:03+0000) PHP Directory Functions PHP Directory Introduction The directory functions allow you to retrieve information about directories and their contents. Installation The directory functions are part of the PHP core. There is no installation needed to use these functions. PHP Directory Functions PHP: indicates the earliest version of PHP that supports the function. Function Description chdir() Changes the current directory chroot() Changes the root directory of the current process dir() Opens a directory handle and returns an object closedir() Closes a directory handle getcwd() Returns the current directory opendir() Opens a directory handle

PHP 3 4 3 3 4 3

22

readdir() rewinddir() scandir()

Returns an entry from a directory handle Resets a directory handle Lists files and directories inside a specified path

PHP Directory Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description DIRECTORY_SEPARATOR PATH_SEPARATOR

3 3 5

PHP 3 4

PHP Error and Logging Functions The error and logging functions allows error handling and logging. The error functions allow users to define error handling rules, and modify the way the errors can be logged. The logging functions allow users to log applications and send log messages to email, system logs or other machines. Installation The error and logging functions are part of the PHP core. There is no installation needed to use these functions. PHP Error and Logging Functions PHP: indicates the earliest version of PHP that supports the function. Function Description debug_backtrace() Generates a backtrace debug_print_backtrace() Prints a backtrace error_get_last() Gets the last error occurred error_log() Sends an error to the server error-log, to a file or to a remote destination error_reporting() Specifies which errors are reported restore_error_handler() Restores the previous error handler restore_exception_handler() Restores the previous exception handler set_error_handler() Sets a user-defined function to handle errors set_exception_handler() Sets a user-defined function to handle exceptions trigger_error() Creates a user-defined error message user_error()

Alias of trigger_error()

PHP 4 5 5 4 4 4 5 4 5 4 4

PHP Error and Logging Constants PHP: indicates the earliest version of PHP that supports the constant. Value Constant Description PHP 1 E_ERROR Fatal run-time errors. Errors that cannot be recovered from. Execution of the script is halted 2 E_WARNING Non-fatal run-time errors. Execution of the script is not halted 4 E_PARSE Compile-time parse errors. Parse errors should only be generated by the parser 8 E_NOTICE Run-time notices. The script found something that might be an error, but could also happen when running a script normally 16 E_CORE_ERROR Fatal errors at PHP startup. This is like an E_ERROR in 4 the PHP core 32 E_CORE_WARNING Non-fatal errors at PHP startup. This is like an 4 E_WARNING in the PHP core

23

64

E_COMPILE_ERROR

128

E_COMPILE_WARNING

256

E_USER_ERROR

512

E_USER_WARNING

1024

E_USER_NOTICE

2048

E_STRICT

4096

E_RECOVERABLE_ERROR

8191

E_ALL

Fatal compile-time errors. This is like an E_ERROR 4 generated by the Zend Scripting Engine Non-fatal compile-time errors. This is like an 4 E_WARNING generated by the Zend Scripting Engine Fatal user-generated error. This is like an E_ERROR set 4 by the programmer using the PHP function trigger_error() Non-fatal user-generated warning. This is like an 4 E_WARNING set by the programmer using the PHP function trigger_error() User-generated notice. This is like an E_NOTICE set by 4 the programmer using the PHP function trigger_error() Run-time notices. PHP suggest changes to your code to 5 help interoperability and compatibility of the code Catchable fatal error. This is like an E_ERROR but can 5 be caught by a user defined handle (see also set_error_handler()) All errors and warnings, except of level E_STRICT 5

PHP Filesystem Functions PHP Filesystem Introduction The filesystem functions allow you to access and manipulate the filesystem. Installation The filesystem functions are part of the PHP core. There is no installation needed to use these functions. Runtime Configuration The behavior of the filesystem functions is affected by settings in php.ini. Filesystem configuration options: Name Default Description allow_url_fopen "1" Allows fopen()-type functions to work with URLs (available since PHP 4.0.4) user_agent NULL Defines the user agent for PHP to send (available since PHP 4.3) default_socket_timeout "60" Sets the default timeout, in seconds, for socket based streams (available since PHP 4.3) from "" Defines the anonymous FTP password (your email address) auto_detect_line_endings "0" When set to "1", PHP will examine the data read by fgets() and file() to see if it is using Unix, MS-Dos or Mac line-ending characters (available since PHP 4.3)

Changeable PHP_INI_SYSTEM PHP_INI_ALL PHP_INI_ALL

PHP_INI_ALL PHP_INI_ALL

Unix / Windows Compatibility When specifying a path on Unix platforms, the forward slash (/) is used as directory separator. However, on Windows platforms, both forward slash (/) and backslash (\) can be used. PHP Filesystem Functions PHP: indicates the earliest version of PHP that supports the function. Function Description basename() Returns the filename component of a path chgrp() Changes the file group chmod() Changes the file mode chown() Changes the file owner clearstatcache() Clears the file status cache

PHP 3 3 3 3 3

24

copy() delete() dirname() disk_free_space() disk_total_space() diskfreespace() fclose() feof() fflush() fgetc() fgetcsv() fgets() fgetss() file() file_exists() file_get_contents() file_put_contents fileatime() filectime() filegroup() fileinode() filemtime() fileowner() fileperms() filesize() filetype() flock() fnmatch() fopen() fpassthru() fputcsv() fputs() fread() fscanf() fseek() fstat() ftell() ftruncate() fwrite() glob() is_dir() is_executable() is_file() is_link() is_readable() is_uploaded_file() is_writable() is_writeable()

Copies a file See unlink() or unset() Returns the directory name component of a path Returns the free space of a directory Returns the total size of a directory Alias of disk_free_space() Closes an open file Tests for end-of-file on an open file Flushes buffered output to an open file Returns a character from an open file Parses a line from an open file, checking for CSV fields Returns a line from an open file Returns a line, with HTML and PHP tags removed, from an open file Reads a file into an array Checks whether or not a file or directory exists Reads a file into a string Writes a string to a file Returns the last access time of a file Returns the last change time of a file Returns the group ID of a file Returns the inode number of a file Returns the last modification time of a file Returns the user ID (owner) of a file Returns the permissions of a file Returns the file size Returns the file type Locks or releases a file Matches a filename or string against a specified pattern Opens a file or URL Reads from an open file, until EOF, and writes the result to the output buffer Formats a line as CSV and writes it to an open file Alias of fwrite() Reads from an open file Parses input from an open file according to a specified format Seeks in an open file Returns information about an open file Returns the current position in an open file Truncates an open file to a specified length Writes to an open file Returns an array of filenames / directories matching a specified pattern Checks whether a file is a directory Checks whether a file is executable Checks whether a file is a regular file Checks whether a file is a link Checks whether a file is readable Checks whether a file was uploaded via HTTP POST Checks whether a file is writeable Alias of is_writable()

3 3 4 4 3 3 3 4 3 3 3 3 3 3 4 5 3 3 3 3 3 3 3 3 3 3 4 3 3 5 3 3 4 3 4 3 4 3 4 3 3 3 3 3 3 4 3

25

link() linkinfo() lstat() mkdir() move_uploaded_file() parse_ini_file() pathinfo() pclose() popen() readfile() readlink() realpath() rename() rewind() rmdir() set_file_buffer() stat() symlink() tempnam() tmpfile() touch() umask() unlink()

Creates a hard link Returns information about a hard link Returns information about a file or symbolic link Creates a directory Moves an uploaded file to a new location Parses a configuration file Returns information about a file path Closes a pipe opened by popen() Opens a pipe Reads a file and writes it to the output buffer Returns the target of a symbolic link Returns the absolute pathname Renames a file or directory Rewinds a file pointer Removes an empty directory Sets the buffer size of an open file Returns information about a file Creates a symbolic link Creates a unique temporary file Creates a unique temporary file Sets access and modification time of a file Changes file permissions for files Deletes a file

PHP Filesystem Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description GLOB_BRACE GLOB_ONLYDIR GLOB_MARK GLOB_NOSORT GLOB_NOCHECK GLOB_NOESCAPE PATHINFO_DIRNAME PATHINFO_BASENAME PATHINFO_EXTENSION FILE_USE_INCLUDE_PATH FILE_APPEND FILE_IGNORE_NEW_LINES FILE_SKIP_EMPTY_LINES

3 3 3 3 4 4 4 3 3 3 3 4 3 3 3 3 3 3 3 3 3 3 3

PHP

PHP Filter Functions PHP Filter Introduction This PHP filters is used to validate and filter data coming from insecure sources, like user input. Installation The filter functions are part of the PHP core. There is no installation needed to use these functions. PHP Filter Functions PHP: indicates the earliest version of PHP that supports the function. Function Description

PHP

26

filter_has_var() filter_id() filter_input() filter_input_array() filter_list() filter_var_array() filter_var()

Checks if a variable of a specified input type exist Returns the ID number of a specified filter Get input from outside the script and filter it Get multiple inputs from outside the script and filters them Returns an array of all supported filters Get multiple variables and filter them Get a variable and filter it

PHP Filters ID Name FILTER_CALLBACK FILTER_SANITIZE_STRING FILTER_SANITIZE_STRIPPED FILTER_SANITIZE_ENCODED FILTER_SANITIZE_SPECIAL_CHARS FILTER_SANITIZE_EMAIL FILTER_SANITIZE_URL FILTER_SANITIZE_NUMBER_INT FILTER_SANITIZE_NUMBER_FLOAT FILTER_SANITIZE_MAGIC_QUOTES FILTER_UNSAFE_RAW FILTER_VALIDATE_INT FILTER_VALIDATE_BOOLEAN FILTER_VALIDATE_FLOAT FILTER_VALIDATE_REGEXP FILTER_VALIDATE_URL FILTER_VALIDATE_EMAIL FILTER_VALIDATE_IP

5 5 5 5 5 5 5

Description Call a user-defined function to filter data Strip tags, optionally strip or encode special characters Alias of "string" filter URL-encode string, optionally strip or encode special characters HTML-escape '"<>& and characters with ASCII value less than 32 Remove all characters, except letters, digits and !#$ %&'*+-/=?^_`{|}~@.[] Remove all characters, except letters, digits and $-_.+! *'(),{}|\\^~[]`<>#%";/?:@&= Remove all characters, except digits and +Remove all characters, except digits, +- and optionally .,eE Apply addslashes() Do nothing, optionally strip or encode special characters Validate value as integer, optionally from the specified range Return TRUE for "1", "true", "on" and "yes", FALSE for "0", "false", "off", "no", and "", NULL otherwise Validate value as float Validate value against regexp, a Perl-compatible regular expression Validate value as URL, optionally with required components Validate value as e-mail Validate value as IP address, optionally only IPv4 or IPv6 or not from private or reserved ranges

PHP FTP Functions PHP FTP Introduction The FTP functions give client access to file servers through the File Transfer Protocol (FTP). The FTP functions are used to open, login and close connections, as well as upload, download, rename, delete, and get information on files from file servers. Not all of the FTP functions will work with every server or return the same results. The FTP functions became available with PHP 3. These functions are meant for detailed access to an FTP server. If you only wish to read from or write to a file on an FTP server, consider using the ftp:// wrapper with the Filesystem functions. Installation The windows version of PHP has built-in support for the FTP extension. So, the FTP functions will work automatically.

27

However, if you are running the Linux version of PHP, you will have to compile PHP with --enable-ftp (PHP 4+) or --with-ftp (PHP 3) to get the FTP functions to work. PHP FTP Functions PHP: indicates the earliest version of PHP that supports the function. Function Description PHP ftp_alloc() Allocates space for a file to be uploaded to the FTP server 5 ftp_cdup() Changes the current directory to the parent directory on the FTP 3 server ftp_chdir() Changes the current directory on the FTP server 3 ftp_chmod() Sets permissions on a file via FTP 5 ftp_close() Closes an FTP connection 4 ftp_connect() Opens an FTP connection 3 ftp_delete() Deletes a file on the FTP server 3 ftp_exec() Executes a program/command on the FTP server 4 ftp_fget() Downloads a file from the FTP server and saves it to an open file 3 ftp_fput() Uploads from an open file and saves it to a file on the FTP server 3 ftp_get_option() Returns runtime behaviors of the FTP connection 4 ftp_get() Downloads a file from the FTP server 3 ftp_login() Logs on to an FTP connection 3 ftp_mdtm() Returns the last modified time of a specified file 3 ftp_mkdir() Creates a new directory on the FTP server 3 ftp_nb_continue() Continues retrieving/sending a file (non-blocking) 4 ftp_nb_fget() Downloads a file from the FTP server and saves it to an open file (non-4 blocking) ftp_nb_fput() Uploads from an open file and saves it to a file on the FTP server 4 (non-blocking) ftp_nb_get() Downloads a file from the FTP server (non-blocking) 4 ftp_nb_put() Uploads a file to the FTP server (non-blocking) 4 ftp_nlist() Lists the files in a specified directory on the FTP server 3 ftp_pasv() Turns passive mode on or off 3 ftp_put() Uploads a file to the FTP server 3 ftp_pwd() Returns the current directory name 3 ftp_quit() Alias of ftp_close() 3 ftp_raw() Sends a raw command to the FTP server 5 ftp_rawlist() Returns a detailed list of files in the specified directory 3 ftp_rename() Renames a file or directory on the FTP server 3 ftp_rmdir() Removes a directory on the FTP server 3 ftp_set_option() Sets runtime options for the FTP connection 4 ftp_site() Sends a SITE command to the server 3 ftp_size() Returns the size of the specified file 3 ftp_ssl_connect() Opens a secure SSL-FTP connection 4 ftp_systype() Returns the system type identifier of the FTP server 3

PHP FTP Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description FTP_ASCII FTP_TEXT FTP_BINARY FTP_IMAGE

PHP 3 3 3 3

28

FTP_TIMEOUT_SEC FTP_AUTOSEEK FTP_AUTORESUME FTP_FAILED FTP_FINISHED FTP_MOREDATA

3 4 Determine resume position and start position for get and put requests 4 automatically Asynchronous transfer has failed 4 Asynchronous transfer has finished 4 Asynchronous transfer is still active 4

PHP HTTP Functions PHP HTTP Introduction The HTTP functions let you manipulate information sent to the browser by the Web server, before any other output has been sent. Installation The directory functions are part of the PHP core. There is no installation needed to use these functions. PHP HTTP Functions PHP: indicates the earliest version of PHP that supports the function. Function Description header() Sends a raw HTTP header to a client headers_list() Returns a list of response headers sent (or ready to send) headers_sent() Checks if / where the HTTP headers have been sent setcookie() Sends an HTTP cookie to a client setrawcookie() Sends an HTTP cookie without URL encoding the cookie value

PHP 3 5 3 3 5

PHP HTTP Constants None. PHP libxml Functions PHP libxml Introduction The libxml functions and constants are used together with SimpleXML, XSLT and DOM functions. Installation These functions require the libxml package. Download at xmlsoft.org PHP libxml Functions PHP: indicates the earliest version of PHP that supports the function. Function Description libxml_clear_errors() Clear libxml error buffer libxml_get_errors() Retrieve array of errors libxml_get_last_error() Retrieve last error from libxml libxml_set_streams_context() Set the streams context for the next libxml document load or write libxml_use_internal_errors() Disable libxml errors and allow user to fetch error information as needed PHP libxml Constants Function LIBXML_COMPACT LIBXML_DTDATTR LIBXML_DTDLOAD LIBXML_DTDVALID

Description Set small nodes allocation optimization. This may improve the application performance Set default DTD attributes Load external subset Validate with the DTD

PHP 5 5 5 5 5

PHP 5 5 5 5

29

LIBXML_NOBLANKS LIBXML_NOCDATA LIBXML_NOEMPTYTAG

LIBXML_NOENT LIBXML_NOERROR LIBXML_NONET LIBXML_NOWARNING LIBXML_NOXMLDECL LIBXML_NSCLEAN LIBXML_XINCLUDE LIBXML_ERR_ERROR LIBXML_ERR_FATAL LIBXML_ERR_NONE LIBXML_ERR_WARNING LIBXML_VERSION LIBXML_DOTTED_VERSION

Remove blank nodes Set CDATA as text nodes Change empty tags (e.g.
to

), only available in the DOMDocument->save() and DOMDocument>saveXML() functions Substitute entities Do not show error reports Stop network access while loading documents Do not show warning reports Drop the XML declaration when saving a document Remove excess namespace declarations Use XInclude substitution Get recoverable errors Get fatal errors Get no errors Get simple warnings Get libxml version (e.g. 20605 or 20617) Get dotted libxml version (e.g. 2.6.5 or 2.6.17)

5 5 5

5 5 5 5 5 5 5 5 5 5 5 5 5

PHP Mail Functions PHP Mail Introduction The mail() function allows you to send emails directly from a script. Requirements For the mail functions to be available, PHP requires an installed and working email system. The program to be used is defined by the configuration settings in the php.ini file. Installation The mail functions are part of the PHP core. There is no installation needed to use these functions. Runtime Configuration The behavior of the mail functions is affected by settings in the php.ini file. Mail configuration options: Name Default Description SMTP "localhost" Windows only: The DNS name or IP address of the SMTP server smtp_port "25" Windows only: The SMTP port number. Available since PHP 4.3 sendmail_from NULL Windows only: Specifies the "from" address to be used in email sent from PHP sendmail_path NULL Unix systems only: Specifies where the sendmail program can be found (usually /usr/sbin/sendmail or /usr/lib/sendmail)

Changeable PHP_INI_ALL PHP_INI_ALL PHP_INI_ALL PHP_INI_SYSTEM

PHP Mail Functions PHP: indicates the earliest version of PHP that supports the function. Function Description ezmlm_hash() Calculates the hash value needed by the EZMLM mailing list system mail() Allows you to send emails directly from a script

PHP 3 3

PHP Mail Constants None. PHP Math Functions

30

PHP Math Introduction The math functions can handle values within the range of integer and float types. Installation The math functions are part of the PHP core. There is no installation needed to use these functions. PHP Math Functions PHP: indicates the earliest version of PHP that supports the function. Function Description PHP abs() Returns the absolute value of a number 3 acos() Returns the arccosine of a number 3 acosh() Returns the inverse hyperbolic cosine of a number 4 asin() Returns the arcsine of a number 3 asinh() Returns the inverse hyperbolic sine of a number 4 atan() Returns the arctangent of a number as a numeric value between -PI/2 3 and PI/2 radians atan2() Returns the angle theta of an (x,y) point as a numeric value between 3 -PI and PI radians atanh() Returns the inverse hyperbolic tangent of a number 4 base_convert() Converts a number from one base to another 3 bindec() Converts a binary number to a decimal number 3 ceil() Returns the value of a number rounded upwards to the nearest integer 3 cos() Returns the cosine of a number 3 cosh() Returns the hyperbolic cosine of a number 4 decbin() Converts a decimal number to a binary number 3 dechex() Converts a decimal number to a hexadecimal number 3 decoct() Converts a decimal number to an octal number 3 deg2rad() Converts a degree to a radian number 3 exp() Returns the value of Ex 3 x expm1() Returns the value of E - 1 4 floor() Returns the value of a number rounded downwards to the nearest 3 integer fmod() Returns the remainder (modulo) of the division of the arguments 4 getrandmax() Returns the maximum random number that can be returned by a call 3 to the rand() function hexdec() Converts a hexadecimal number to a decimal number 3 hypot() Returns the length of the hypotenuse of a right-angle triangle 4 is_finite() Returns true if a value is a finite number 4 is_infinite() Returns true if a value is an infinite number 4 is_nan() Returns true if a value is not a number 4 lcg_value() Returns a pseudo random number in the range of (0,1) 4 log() Returns the natural logarithm (base E) of a number 3 log10() Returns the base-10 logarithm of a number 3 log1p() Returns log(1+number) 4 max() Returns the number with the highest value of two specified numbers 3 min() Returns the number with the lowest value of two specified numbers 3 mt_getrandmax() Returns the largest possible value that can be returned by mt_rand() 3 mt_rand() Returns a random integer using Mersenne Twister algorithm 3 mt_srand() Seeds the Mersenne Twister random number generator 3 octdec() Converts an octal number to a decimal number 3 pi() Returns the value of PI 3 pow() Returns the value of x to the power of y 3

31

rad2deg() rand() round() sin() sinh() sqrt() srand() tan() tanh()

Converts a radian number to a degree Returns a random integer Rounds a number to the nearest integer Returns the sine of a number Returns the hyperbolic sine of a number Returns the square root of a number Seeds the random number generator Returns the tangent of an angle Returns the hyperbolic tangent of an angle

3 3 3 3 4 3 3 3 4

PHP Math Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description M_E Returns e (approx. 2.718) M_EULER Returns Euler's constant (approx. 0.577) M_LNPI Returns the natural logarithm of PI (approx. 1.144) M_LN2 Returns the natural logarithm of 2 (approx. 0.693) M_LN10 Returns the natural logarithm of 10 (approx. 2.302) M_LOG2E Returns the base-2 logarithm of E (approx. 1.442) M_LOG10E Returns the base-10 logarithm of E (approx. 0.434) M_PI Returns PI (approx. 3.14159) M_PI_2 Returns PI/2 (approx. 1.570) M_PI_4 Returns PI/4 (approx. 0.785) M_1_PI Returns 1/PI (approx. 0.318) M_2_PI Returns 2/PI (approx. 0.636) M_SQRTPI Returns the square root of PI (approx. 1.772) M_2_SQRTPI Returns 2/square root of PI (approx. 1.128) M_SQRT1_2 Returns the square root of 1/2 (approx. 0.707) M_SQRT2 Returns the square root of 2 (approx. 1.414) M_SQRT3 Returns the square root of 3 (approx. 1.732)

PHP 4 4 4 4 4 4 4 3 4 4 4 4 4 4 4 4 4

PHP Misc. Functions PHP Miscellaneous Introduction The misc. functions were only placed here because none of the other categories seemed to fit. Installation The misc functions are part of the PHP core. There is no installation needed to use these functions. Runtime Configuration The behavior of the misc functions is affected by settings in the php.ini file. Misc. configuration options: Name Default Description ignore_user_abort "0" FALSE indicates that scripts will be terminated as soon as they try to output something after a client has aborted their connection highlight.string "#DD0000" Color for highlighting a string in PHP syntax highlight.comment "#FF8000" Color for highlighting PHP comments highlight.keyword "#007700" Color for syntax highlighting PHP keywords (e.g. parenthesis and semicolon) highlight.bg "#FFFFFF" Color for background highlight.default "#0000BB" Default color for PHP syntax highlight.html "#000000" Color for HTML code

Changeable PHP_INI_ALL

PHP_INI_ALL PHP_INI_ALL PHP_INI_ALL PHP_INI_ALL PHP_INI_ALL PHP_INI_ALL

32

browscap

NULL

Name and location of browser-capabilities file PHP_INI_SYSTEM (e.g. browscap.ini)

PHP Misc. Functions PHP: indicates the earliest version of PHP that supports the function. Function Description connection_aborted() Checks whether the client has disconnected connection_status() Returns the current connection status connection_timeout() Deprecated in PHP 4.0.5 constant() Returns the value of a constant define() Defines a constant defined() Checks whether a constant exists die() Prints a message and exits the current script eval() Evaluates a string as PHP code exit() Prints a message and exits the current script get_browser() Returns the capabilities of the user's browser highlight_file() Outputs a file with the PHP syntax highlighted highlight_string() Outputs a string with the PHP syntax highlighted ignore_user_abort() Sets whether a remote client can abort the running of a script pack() Packs data into a binary string php_check_syntax() Deprecated in PHP 5.0.5 php_strip_whitespace() Returns the source code of a file with PHP comments and whitespace removed show_source() Alias of highlight_file() sleep() Delays code execution for a number of seconds time_nanosleep() Delays code execution for a number of seconds and nanoseconds time_sleep_until() Delays code execution until a specified time uniqid() Generates a unique ID unpack() Unpacks data from a binary string usleep() Delays code execution for a number of microseconds

PHP Misc. Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description CONNECTION_ABORTED CONNECTION_NORMAL CONNECTION_TIMEOUT __COMPILER_HALT_OFFSET__

PHP 3 3 3 4 3 3 3 3 3 3 4 4 3 3 5 5 4 3 5 5 3 3 3

PHP

5

PHP MySQL Functions PHP MySQL Introduction The MySQL functions allows you to access MySQL database servers. Installation For the MySQL functions to be available, you must compile PHP with MySQL support. For compiling, use --with-mysql=DIR (the optional DIR points to the MySQL directory). Note: For full functionality of MySQL versions greater than 4.1., use the MySQLi extension instead. If you would like to install both the mysql extension and the mysqli extension you should use the same client library to avoid any conflicts. Installation on Linux Systems

33

PHP 5+: MySQL and the MySQL library is not enabled by default. Use the --with-mysql=DIR configure option to include MySQL support and download headers and libraries from www.mysql.com. Installation on Windows Systems PHP 5+: MySQL is not enabled by default, so the php_mysql.dll must be enabled inside of php.ini. Also, PHP needs access to the MySQL client library. A file named libmysql.dll is included in the Windows PHP distribution, and in order for PHP to talk to MySQL this file needs to be available to the Windows systems PATH. To enable any PHP extension, the PHP extension_dir setting (in the php.ini file) should be set to the directory where the PHP extensions are located. An example extension_dir value is c:\php\ext. Note: If you get the following error when starting the web server: "Unable to load dynamic library './php_mysql.dll'", this is because php_mysql.dll or libmysql.dll cannot be found by the system. Runtime Configuration The behavior of the MySQL functions is affected by settings in the php.ini file. MySQL configuration options: Name Default Description Changeable mysql.allow_persistent "1" Whether or not to allow persistent PHP_INI_SYSTEM connections mysql.max_persistent "-1" The maximum number of persistent PHP_INI_SYSTEM connections per process mysql.max_links "-1" The maximum number of connections per PHP_INI_SYSTEM process (persistent connections included) mysql.trace_mode "0" Trace mode. When set to "1", warnings and PHP_INI_ALL SQL-errors will be displayed. Available since PHP 4.3 mysql.default_port NULL The default TCP port number to use PHP_INI_ALL mysql.default_socket NULL The default socket name to use. Available PHP_INI_ALL since PHP 4.0.1 mysql.default_host NULL The default server host to use (doesn't apply PHP_INI_ALL in SQL safe mode) mysql.default_user NULL The default user name to use (doesn't apply PHP_INI_ALL in SQL safe mode) mysql.default_password NULL The default password to use (doesn't apply PHP_INI_ALL in SQL safe mode) mysql.connect_timeout "60" Connection timeout in seconds PHP_INI_ALL

Resource Types There are two resource types used in the MySQL extension. The first one is the link_identifier for a database connection, the second is a resource which holds the result of a query. Note: Most MySQL functions accept link_identifier as the last optional parameter. If it is not provided, the last opened connection is used. PHP MySQL Functions PHP: indicates the earliest version of PHP that supports the function. Function Description mysql_affected_rows() Returns the number of affected rows in the previous MySQL operation mysql_change_user() Deprecated. Changes the user of the current MySQL connection mysql_client_encoding() Returns the name of the character set for the current connection mysql_close() Closes a non-persistent MySQL connection mysql_connect() Opens a non-persistent MySQL connection mysql_create_db() Deprecated. Creates a new MySQL database. Use mysql_query() instead mysql_data_seek() Moves the record pointer mysql_db_name() Returns a database name from a call to mysql_list_dbs()

PHP 3 3 4 3 3 3 3 3

34

mysql_db_query() mysql_drop_db() mysql_errno() mysql_error() mysql_escape_string() mysql_fetch_array() mysql_fetch_assoc() mysql_fetch_field() mysql_fetch_lengths() mysql_fetch_object() mysql_fetch_row() mysql_field_flags() mysql_field_len() mysql_field_name() mysql_field_seek() mysql_field_table() mysql_field_type() mysql_free_result() mysql_get_client_info() mysql_get_host_info() mysql_get_proto_info() mysql_get_server_info() mysql_info() mysql_insert_id() mysql_list_dbs() mysql_list_fields() mysql_list_processes() mysql_list_tables() mysql_num_fields() mysql_num_rows() mysql_pconnect() mysql_ping() mysql_query() mysql_real_escape_string() mysql_result() mysql_select_db() mysql_stat() mysql_tablename() mysql_thread_id() mysql_unbuffered_query()

Deprecated. Sends a MySQL query. Use mysql_select_db() and 3 mysql_query() instead Deprecated. Deletes a MySQL database. Use mysql_query() 3 instead Returns the error number of the last MySQL operation 3 Returns the error description of the last MySQL operation 3 Deprecated. Escapes a string for use in a mysql_query. Use 4 mysql_real_escape_string() instead Returns a row from a recordset as an associative array and/or a 3 numeric array Returns a row from a recordset as an associative array 4 Returns column info from a recordset as an object 3 Returns the length of the contents of each field in a result row 3 Returns a row from a recordset as an object 3 Returns a row from a recordset as a numeric array 3 Returns the flags associated with a field in a recordset 3 Returns the maximum length of a field in a recordset 3 Returns the name of a field in a recordset 3 Moves the result pointer to a specified field 3 Returns the name of the table the specified field is in 3 Returns the type of a field in a recordset 3 Free result memory 3 Returns MySQL client info 4 Returns MySQL host info 4 Returns MySQL protocol info 4 Returns MySQL server info 4 Returns information about the last query 4 Returns the AUTO_INCREMENT ID generated from the previous 3 INSERT operation Lists available databases on a MySQL server 3 Deprecated. Lists MySQL table fields. Use mysql_query() 3 instead Lists MySQL processes 4 Deprecated. Lists tables in a MySQL database. Use 3 mysql_query() instead Returns the number of fields in a recordset 3 Returns the number of rows in a recordset 3 Opens a persistent MySQL connection 3 Pings a server connection or reconnects if there is no connection 4 Executes a query on a MySQL database 3 Escapes a string for use in SQL statements 4 Returns the value of a field in a recordset 3 Sets the active MySQL database 3 Returns the current system status of the MySQL server 4 Deprecated. Returns the table name of field. Use mysql_query() 3 instead Returns the current thread ID 4 Executes a query on a MySQL database (without fetching / 4 buffering the result)

PHP MySQL Constants

35

Since PHP 4.3 it has been possible to specify additional flags for the mysql_connect() and mysql_pconnect() functions: PHP: indicates the earliest version of PHP that supports the constant. Constant Description PHP MYSQL_CLIENT_COMPRESS Use compression protocol 4.3 MYSQL_CLIENT_IGNORE_SPACE Allow space after function names 4.3 MYSQL_CLIENT_INTERACTIVE

Allow interactive timeout seconds of inactivity before 4.3 closing the connection MYSQL_CLIENT_SSL Use SSL encryption (only available with version 4+ of 4.3 the MySQL client library) The mysql_fetch_array() function uses a constant for the different types of result arrays. The following constants are defined: Constant Description PHP MYSQL_ASSOC Columns are returned into the array with the fieldname as the array index MYSQL_BOTH Columns are returned into the array having both a numerical index and the fieldname as the array index MYSQL_NUM Columns are returned into the array having a numerical index (index starts at 0)

PHP SimpleXML Functions PHP SimpleXML Introduction The SimpleXML functions lets you convert XML to an object. This object can be processed, like any other object, with normal property selectors and array iterators. Some of these functions requires the newest PHP build. Installation The SimpleXML functions are part of the PHP core. There is no installation needed to use these functions. PHP SimpleXML Functions PHP: indicates the earliest version of PHP that supports the function. Function Description __construct() Creates a new SimpleXMLElement object addAttribute() Adds an attribute to the SimpleXML element addChild() Adds a child element the SimpleXML element asXML() Gets an XML string from a SimpleXML element attributes() Gets a SimpleXML element's attributes children() Gets the children of a specified node getDocNamespaces() Gets the namespaces of an XML document getName() Gets the name of a SimpleXML element getNamespaces() Gets the namespaces from XML data registerXPathNamespace() Creates a namespace context for the next XPath query simplexml_import_dom() Gets a SimpleXMLElement object from a DOM node simplexml_load_file() Gets a SimpleXMLElement object from an XML document simplexml_load_string() Gets a SimpleXMLElement object from an XML string xpath() Runs an XPath query on XML data

PHP 5 5 5 5 5 5 5 5 5 5 5 5 5 5

PHP SimpleXML Constants None PHP String Functions PHP String Introduction The string functions allow you to manipulate strings.

36

Installation The string functions are part of the PHP core. There is no installation needed to use these functions. PHP String Functions PHP: indicates the earliest version of PHP that supports the function. Function Description PHP addcslashes() Returns a string with backslashes in front of the specified 4 characters addslashes() Returns a string with backslashes in front of predefined 3 characters bin2hex() Converts a string of ASCII characters to hexadecimal values 3 chop() Alias of rtrim() 3 chr() Returns a character from a specified ASCII value 3 chunk_split() Splits a string into a series of smaller parts 3 convert_cyr_string() Converts a string from one Cyrillic character-set to another 3 convert_uudecode() Decodes a uuencoded string 5 convert_uuencode() Encodes a string using the uuencode algorithm 5 count_chars() Returns how many times an ASCII character occurs within a 4 string and returns the information crc32() Calculates a 32-bit CRC for a string 4 crypt() One-way string encryption (hashing) 3 echo() Outputs strings 3 explode() Breaks a string into an array 3 fprintf() Writes a formatted string to a specified output stream 5 get_html_translation_table() Returns the translation table used by htmlspecialchars() and 4 htmlentities() hebrev() Converts Hebrew text to visual text 3 hebrevc() Converts Hebrew text to visual text and new lines (\n) into
html_entity_decode() Converts HTML entities to characters 4 htmlentities() Converts characters to HTML entities 3 htmlspecialchars_decode() Converts some predefined HTML entities to characters 5 htmlspecialchars() Converts some predefined characters to HTML entities 3 implode() Returns a string from the elements of an array 3 join() Alias of implode() 3 levenshtein() Returns the Levenshtein distance between two strings 3 localeconv() Returns locale numeric and monetary formatting information 4 ltrim() Strips whitespace from the left side of a string 3 md5() Calculates the MD5 hash of a string 3 md5_file() Calculates the MD5 hash of a file 4 metaphone() Calculates the metaphone key of a string 4 money_format() Returns a string formatted as a currency string 4 nl_langinfo() Returns specific local information 4 nl2br() Inserts HTML line breaks in front of each newline in a string 3 number_format() Formats a number with grouped thousands 3 ord() Returns the ASCII value of the first character of a string 3 parse_str() Parses a query string into variables 3 print() Outputs a string 3 printf() Outputs a formatted string 3 quoted_printable_decode() Decodes a quoted-printable string 3 quotemeta() Quotes meta characters 3

37

rtrim() setlocale() sha1() sha1_file() similar_text() soundex() sprintf() sscanf() str_ireplace() str_pad() str_repeat() str_replace() str_rot13() str_shuffle() str_split() str_word_count() strcasecmp() strchr() strcmp() strcoll() strcspn() strip_tags() stripcslashes() stripslashes() stripos() stristr() strlen() strnatcasecmp() strnatcmp() strncasecmp() strncmp() strpbrk() strpos() strrchr() strrev() strripos() strrpos() strspn() strstr() strtok() strtolower()

Strips whitespace from the right side of a string 3 Sets locale information 3 Calculates the SHA-1 hash of a string 4 Calculates the SHA-1 hash of a file 4 Calculates the similarity between two strings 3 Calculates the soundex key of a string 3 Writes a formatted string to a variable 3 Parses input from a string according to a format 4 Replaces some characters in a string (case-insensitive) 5 Pads a string to a new length 4 Repeats a string a specified number of times 4 Replaces some characters in a string (case-sensitive) 3 Performs the ROT13 encoding on a string 4 Randomly shuffles all characters in a string 4 Splits a string into an array 5 Count the number of words in a string 4 Compares two strings (case-insensitive) 3 Finds the first occurrence of a string inside another string 3 (alias of strstr()) Compares two strings (case-sensitive) 3 Locale based string comparison 4 Returns the number of characters found in a string before any 3 part of some specified characters are found Strips HTML and PHP tags from a string 3 Unquotes a string quoted with addcslashes() 4 Unquotes a string quoted with addslashes() 3 Returns the position of the first occurrence of a string inside 5 another string (case-insensitive) Finds the first occurrence of a string inside another string 3 (case-insensitive) Returns the length of a string 3 Compares two strings using a "natural order" algorithm (case- 4 insensitive) Compares two strings using a "natural order" algorithm (case- 4 sensitive) String comparison of the first n characters (case-insensitive) 4 String comparison of the first n characters (case-sensitive) 4 Searches a string for any of a set of characters 5 Returns the position of the first occurrence of a string inside 3 another string (case-sensitive) Finds the last occurrence of a string inside another string 3 Reverses a string 3 Finds the position of the last occurrence of a string inside 5 another string (case-insensitive) Finds the position of the last occurrence of a string inside 3 another string (case-sensitive) Returns the number of characters found in a string that 3 contains only characters from a specified charlist Finds the first occurrence of a string inside another string 3 (case-sensitive) Splits a string into smaller strings 3 Converts a string to lowercase letters 3

38

strtoupper() strtr() substr() substr_compare() substr_count() substr_replace() trim() ucfirst() ucwords() vfprintf() vprintf() vsprintf() wordwrap()

Converts a string to uppercase letters Translates certain characters in a string Returns a part of a string Compares two strings from a specified start position (binary safe and optionally case-sensitive) Counts the number of times a substring occurs in a string Replaces a part of a string with another string Strips whitespace from both sides of a string Converts the first character of a string to uppercase Converts the first character of each word in a string to uppercase Writes a formatted string to a specified output stream Outputs a formatted string Writes a formatted string to a variable Wraps a string to a given number of characters

3 3 3 5 4 4 3 3 3 5 4 4 4

PHP String Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description PHP CRYPT_SALT_LENGTH Contains the length of the default encryption method for the system. For standard DES encryption, the length is 2 CRYPT_STD_DES Set to 1 if the standard DES-based encryption with a 2 character salt is supported, 0 otherwise CRYPT_EXT_DES Set to 1 if the extended DES-based encryption with a 9 character salt is supported, 0 otherwise CRYPT_MD5 Set to 1 if the MD5 encryption with a 12 character salt starting with $1$ is supported, 0 otherwise CRYPT_BLOWFISH Set to 1 if the Blowfish encryption with a 16 character salt starting with $2$ or $2a$ is supported, 0 otherwise0 HTML_SPECIALCHARS HTML_ENTITIES ENT_COMPAT ENT_QUOTES ENT_NOQUOTES CHAR_MAX LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_ALL LC_MESSAGES STR_PAD_LEFT STR_PAD_RIGHT STR_PAD_BOTH PHP XML Parser Functions PHP XML Parser Introduction The XML functions lets you parse, but not validate, XML documents. XML is a data format for standardized structured document exchange. More information on XML can be found in our XML Tutorial. This extension uses the Expat XML parser.

39

Expat is an event-based parser, it views an XML document as a series of events. When an event occurs, it calls a specified function to handle it. Expat is a non-validating parser, and ignores any DTDs linked to a document. However, if the document is not well formed it will end with an error message. Because it is an event-based, non validating parser, Expat is fast and well suited for web applications. The XML parser functions lets you create XML parsers and define handlers for XML events. Installation The XML functions are part of the PHP core. There is no installation needed to use these functions. PHP XML Parser Functions PHP: indicates the earliest version of PHP that supports the function. Function Description PHP utf8_decode() Decodes an UTF-8 string to ISO-8859-1 3 utf8_encode() Encodes an ISO-8859-1 string to UTF-8 3 xml_error_string() Gets an error string from the XML parser 3 xml_get_current_byte_index() Gets the current byte index from the XML 3 parser xml_get_current_column_number() Gets the current column number from the 3 XML parser xml_get_current_line_number() Gets the current line number from the XML 3 parser xml_get_error_code() Gets an error code from the XML parser 3 xml_parse() Parses an XML document 3 xml_parse_into_struct() Parse XML data into an array 3 xml_parser_create_ns() Create an XML parser with namespace 4 support xml_parser_create() Create an XML parser 3 xml_parser_free() Free an XML parser 3 xml_parser_get_option() Get options from an XML parser 3 xml_parser_set_option() Set options in an XML parser 3 xml_set_character_data_handler() Set handler function for character data 3 xml_set_default_handler() Set default handler function 3 xml_set_element_handler() Set handler function for start and end element 3 of elements xml_set_end_namespace_decl_handler() Set handler function for the end of namespace 4 declarations xml_set_external_entity_ref_handler() Set handler function for external entities 3 xml_set_notation_decl_handler() Set handler function for notation declarations 3 xml_set_object() Use XML Parser within an object 4 xml_set_processing_instruction_handler() Set handler function for processing instruction 3 xml_set_start_namespace_decl_handler() Set handler function for the start of 4 namespace declarations xml_set_unparsed_entity_decl_handler() Set handler function for unparsed entity 3 declarations

PHP XML Parser Constants Constant XML_ERROR_NONE (integer) XML_ERROR_NO_MEMORY (integer) XML_ERROR_SYNTAX (integer) XML_ERROR_NO_ELEMENTS (integer) XML_ERROR_INVALID_TOKEN (integer)

40

XML_ERROR_UNCLOSED_TOKEN (integer) XML_ERROR_PARTIAL_CHAR (integer) XML_ERROR_TAG_MISMATCH (integer) XML_ERROR_DUPLICATE_ATTRIBUTE (integer) XML_ERROR_JUNK_AFTER_DOC_ELEMENT (integer) XML_ERROR_PARAM_ENTITY_REF (integer) XML_ERROR_UNDEFINED_ENTITY (integer) XML_ERROR_RECURSIVE_ENTITY_REF (integer) XML_ERROR_ASYNC_ENTITY (integer) XML_ERROR_BAD_CHAR_REF (integer) XML_ERROR_BINARY_ENTITY_REF (integer) XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF (integer) XML_ERROR_MISPLACED_XML_PI (integer) XML_ERROR_UNKNOWN_ENCODING (integer) XML_ERROR_INCORRECT_ENCODING (integer) XML_ERROR_UNCLOSED_CDATA_SECTION (integer) XML_ERROR_EXTERNAL_ENTITY_HANDLING (integer) XML_OPTION_CASE_FOLDING (integer) XML_OPTION_TARGET_ENCODING (integer) XML_OPTION_SKIP_TAGSTART (integer) XML_OPTION_SKIP_WHITE (integer) PHP Zip File Functions PHP: indicates the earliest version of PHP that supports the function. Function Description zip_close() Closes a ZIP file zip_entry_close() Closes an entry in the ZIP file zip_entry_compressedsize() Returns the compressed size of an entry in the ZIP file zip_entry_compressionmethod() Returns the compression method of an entry in the ZIP file zip_entry_filesize() Returns the actual file size of an entry in the ZIP file zip_entry_name() Returns the name of an entry in the ZIP file zip_entry_open() Opens an entry in the ZIP file for reading zip_entry_read() Reads from an open entry in the ZIP file zip_open() Opens a ZIP file zip_read() Reads the next entry in a ZIP file

PHP 4 4 4 4 4 4 4 4 4 4

PHP Calendar Functions PHP: indicates the earliest version of PHP that supports the function. PHP Calendar Introduction The calendar functions are useful when working with different calendar formats. The standard it is based on is the Julian day count (Julian day count is a count of days starting from January 1, 4713 B.C.). Note that the Julian day count is not the same as the Julian calendar! Note: To convert between calendar formats, you must first convert to Julian day count, then to the calendar format. Installation The windows version of PHP has built-in support for the calendar extension. So, the calendar functions will work automatically. However, if you are running the Linux version of PHP, you will have to compile PHP with --enable-calendar to get the calendar functions to work. Function

Description

PHP

41

cal_days_in_month()

4

cal_from_jd()

Returns the number of days in a month for a specified year and calendar Converts a Julian day count into a date of a specified calendar

cal_info()

Returns information about a given calendar

4

cal_to_jd()

Converts a date to Julian day count

4

easter_date()

3

FrenchToJD()

Returns the Unix timestamp for midnight on Easter of a specified year Returns the number of days after March 21, on which Easter falls for a specified year Converts a French Republican date to a Julian day count

GregorianToJD()

Converts a Gregorian date to a Julian day count

3

JDDayOfWeek()

Returns the day of a week

3

JDMonthName()

Returns a month name

3

JDToFrench()

Converts a Julian day count to a French Republican date

3

JDToGregorian()

Converts a Julian day count to a Gregorian date

3

jdtojewish()

Converts a Julian day count to a Jewish date

3

JDToJulian()

Converts a Julian day count to a Julian date

3

jdtounix()

Converts a Julian day count to a Unix timestamp

4

JewishToJD()

Converts a Jewish date to a Julian day count

3

JulianToJD()

Converts a Julian date to a Julian day count

3

unixtojd()

Converts a Unix timestamp to a Julian day count

4

easter_days()

PHP Calendar Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description

4

3 3

PHP

CAL_EASTER_ALWAYS_JULIAN

4

CAL_JEWISH_ADD_ALAFIM_GERESH

5

CAL_JEWISH_ADD_ALAFIM

5

CAL_GREGORIAN

Gregorian calendar

3

CAL_JULIAN

Julian calendar

3

CAL_JEWISH

Jewish calendar

3

CAL_FRENCH

French Republican calendar

3

CAL_NUM_CALS

3

CAL_DOW_DAYNO

3

CAL_DOW_SHORT

3

CAL_DOW_LONG

3

CAL_MONTH_GREGORIAN_SHORT

3

CAL_MONTH_GREGORIAN_LONG

3

CAL_MONTH_JULIAN_SHORT

3

CAL_MONTH_JULIAN_LONG

3

CAL_MONTH_JEWISH

3

42

CAL_MONTH_FRENCH

3

CAL_EASTER_DEFAULT

4

CAL_EASTER_DEFAULT

4

CAL_EASTER_ROMAN

4

CAL_EASTER_ALWAYS_GREGORIAN

4

PHP Date / Time Functions PHP Date / Time Introduction The date/time functions allow you to extract and format the date and time on the server. Note: These functions depend on the locale settings of the server! Installation The date/time functions are part of the PHP core. There is no installation needed to use these functions. Runtime Configuration The behavior of the date/time functions is affected by settings in php.ini. Date/Time configuration options:

Name

Default

Description

Changeable

date.default_latitude

"31.7667"

Specifies the default latitude (available since PHP 5). This option is used by date_sunrise() and date_sunset() Specifies the default longitude (available since PHP 5). This option is used by date_sunrise() and date_sunset() Specifies the default sunrise zenith (available since PHP 5). This option is used by date_sunrise() and date_sunset() Specifies the default sunset zenith (available since PHP 5). This option is used by date_sunrise() and

PHP_INI_ALL

date.default_longitude "35.2333"

date.sunrise_zenith

"90.83"

date.sunset_zenith

"90.83"

PHP_INI_ALL

PHP_INI_ALL

PHP_INI_ALL

43

date_sunset() date.timezone

""

Specifies the default timezone (available since PHP 5.1)

PHP_INI_ALL

PHP Date / Time Functions PHP: indicates the earliest version of PHP that supports the function. Function

Description

PHP

checkdate()

Validates a Gregorian date

3

date_default_timezone_get()

Returns the default time zone

5

date_default_timezone_set()

Sets the default time zone

5

date_sunrise()

Returns the time of sunrise for a given day / location

5

date_sunset()

Returns the time of sunset for a given day / location

5

date()

Formats a local time/date

3

getdate()

3

gettimeofday()

Returns an array that contains date and time information for a Unix timestamp Returns an array that contains current time information

gmdate()

Formats a GMT/UTC date/time

3

gmmktime()

Returns the Unix timestamp for a GMT date

3

gmstrftime()

Formats a GMT/UTC time/date according to locale settings

3

idate()

Formats a local time/date as integer

5

localtime()

4

microtime()

Returns an array that contains the time components of a Unix timestamp Returns the microseconds for the current time

mktime()

Returns the Unix timestamp for a date

3

strftime()

Formats a local time/date according to locale settings

3

strptime()

Parses a time/date generated with strftime()

5

strtotime()

Parses an English textual date or time into a Unix timestamp

3

time()

Returns the current time as a Unix timestamp

3

PHP Date / Time Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description DATE_ATOM

Atom (example: 2005-08-15T16:13:03+0000)

DATE_COOKIE

HTTP Cookies (example: Sun, 14 Aug 2005 16:13:03 UTC)

DATE_ISO8601

ISO-8601 (example: 2005-08-14T16:13:03+0000)

DATE_RFC822

RFC 822 (example: Sun, 14 Aug 2005 16:13:03 UTC)

DATE_RFC850

RFC 850 (example: Sunday, 14-Aug-05 16:13:03 UTC)

DATE_RFC1036

RFC 1036 (example: Sunday, 14-Aug-05 16:13:03 UTC)

DATE_RFC1123

RFC 1123 (example: Sun, 14 Aug 2005 16:13:03 UTC)

DATE_RFC2822

RFC 2822 (Sun, 14 Aug 2005 16:13:03 +0000)

3

3

PHP

44

DATE_RSS

RSS (Sun, 14 Aug 2005 16:13:03 UTC)

DATE_W3C

World Wide Web Consortium (example: 2005-0814T16:13:03+0000)

PHP Directory Functions PHP Directory Introduction The directory functions allow you to retrieve information about directories and their contents. Installation The directory functions are part of the PHP core. There is no installation needed to use these functions. PHP Directory Functions PHP: indicates the earliest version of PHP that supports the function.

Function

Description

chdir() chroot() dir() closedir() getcwd() opendir() readdir() rewinddir() scandir()

Changes the current directory Changes the root directory of the current process Opens a directory handle and returns an object Closes a directory handle Returns the current directory Opens a directory handle Returns an entry from a directory handle Resets a directory handle Lists files and directories inside a specified path

PHP Directory Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description

PH P 3 4 3 3 4 3 3 3 5

PHP

DIRECTORY_SEPARATOR

3

PATH_SEPARATOR

4

PHP Error and Logging Functions The error and logging functions allows error handling and logging. The error functions allow users to define error handling rules, and modify the way the errors can be logged. The logging functions allow users to log applications and send log messages to email, system logs or other machines. Installation The error and logging functions are part of the PHP core. There is no installation needed to use these functions. PHP Error and Logging Functions PHP: indicates the earliest version of PHP that supports the function. Function

Description

PHP

debug_backtrace()

Generates a backtrace

4

debug_print_backtrace()

Prints a backtrace

5

error_get_last()

Gets the last error occurred

5

error_log()

Sends an error to the server error-log, to a file or to a remote destination

4

45

error_reporting()

Specifies which errors are reported

4

restore_error_handler()

Restores the previous error handler

4

restore_exception_handler()

Restores the previous exception handler

5

set_error_handler()

Sets a user-defined function to handle errors

4

set_exception_handler()

Sets a user-defined function to handle exceptions

5

trigger_error()

Creates a user-defined error message

4

user_error()

Alias of trigger_error()

4

PHP Error and Logging Constants PHP: indicates the earliest version of PHP that supports the constant. Value Constant Description 1

E_ERROR

2

E_WARNING

4

E_PARSE

8

E_NOTICE

16

E_CORE_ERROR

32

E_CORE_WARNING

64

E_COMPILE_ERROR

128

E_COMPILE_WARNING

256

E_USER_ERROR

512

E_USER_WARNING

1024

E_USER_NOTICE

2048

E_STRICT

4096

E_RECOVERABLE_ERROR

8191

E_ALL

PHP

Fatal run-time errors. Errors that cannot be recovered from. Execution of the script is halted Non-fatal run-time errors. Execution of the script is not halted Compile-time parse errors. Parse errors should only be generated by the parser Run-time notices. The script found something that might be an error, but could also happen when running a script normally Fatal errors at PHP startup. This is like an E_ERROR in the PHP core Non-fatal errors at PHP startup. This is like an E_WARNING in the PHP core Fatal compile-time errors. This is like an E_ERROR generated by the Zend Scripting Engine Non-fatal compile-time errors. This is like an E_WARNING generated by the Zend Scripting Engine Fatal user-generated error. This is like an E_ERROR set by the programmer using the PHP function trigger_error() Non-fatal user-generated warning. This is like an E_WARNING set by the programmer using the PHP function trigger_error() User-generated notice. This is like an E_NOTICE set by the programmer using the PHP function trigger_error() Run-time notices. PHP suggest changes to your code to help interoperability and compatibility of the code Catchable fatal error. This is like an E_ERROR but can be caught by a user defined handle (see also set_error_handler()) All errors and warnings, except of level E_STRICT

PHP Filesystem Functions PHP Filesystem Introduction The filesystem functions allow you to access and manipulate the filesystem. I Installation The filesystem functions are part of the PHP core. There is no installation needed to use these functions. Runtime Configuration The behavior of the filesystem functions is affected by settings in php.ini. Filesystem configuration options:

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Name

Default

Description

allow_url_fopen

"1"

Allows fopen()-type functions to work with URLs (available since PHP 4.0.4)

PHP_INI_SYSTEM

user_agent

NULL

default_socket_timeout

"60"

from

""

Allows fopen()type functions to work with URLs (available since PHP 4.0.4) Defines the user agent for PHP to send (available since PHP 4.3) Defines the user agent for PHP to send (available since PHP 4.3) Sets the default timeout, in seconds, for socket based streams (available since PHP 4.3) Defines the anonymous FTP password (your email address)

Changeable PHP_INI_SYSTEM

PHP_INI_ALL

PHP_INI_ALL

PHP_INI_ALL

PHP_INI_ALL

Unix / Windows Compatibility When specifying a path on Unix platforms, the forward slash (/) is used as directory separator. However, on Windows platforms, both forward slash (/) and backslash (\) can be used. PHP Filesystem Functions PHP: indicates the earliest version of PHP that supports the function.

Function basename() chgrp() chmod() chown() clearstatcache() copy() delete()

Description Returns the filename component of a path Changes the file group Changes the file mode Changes the file owner Clears the file status cache Copies a file See unlink() or unset()

PHP 3 3 3 3 3 3

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dirname() disk_free_space() disk_total_space() diskfreespace() fclose() feof() fflush() fgetc() fgetcsv() fgets() fgetss() file() file_exists() file_get_contents() file_put_contents fileatime() filectime() filegroup() fileinode() filemtime() fileowner() fileperms() filesize() filetype() flock() fnmatch() fopen() fpassthru() fputcsv() fputs() fread() fscanf() fseek() fstat() ftell() ftruncate() fwrite() glob() is_dir()

Returns the directory name component of a path Returns the free space of a directory Returns the total size of a directory Alias of disk_free_space() Closes an open file Tests for end-of-file on an open file Flushes buffered output to an open file Returns a character from an open file Parses a line from an open file, checking for CSV fields Returns a line from an open file Returns a line, with HTML and PHP tags removed, from an open file Reads a file into an array Checks whether or not a file or directory exists Reads a file into a string Writes a string to a file Returns the last access time of a file Returns the last change time of a file Returns the group ID of a file Returns the inode number of a file Returns the last modification time of a file Returns the user ID (owner) of a file Returns the permissions of a file Returns the file size Returns the file type Locks or releases a file Matches a filename or string against a specified pattern Opens a file or URL Reads from an open file, until EOF, and writes the result to the output buffer Formats a line as CSV and writes it to an open file Alias of fwrite() Reads from an open file Parses input from an open file according to a specified format Seeks in an open file Returns information about an open file Returns the current position in an open file Truncates an open file to a specified length Writes to an open file Returns an array of filenames / directories matching a specified pattern Checks whether a file is a directory

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is_executable() is_file() is_link() is_readable() is_uploaded_file() is_writable() is_writeable() link() linkinfo() lstat() mkdir() move_uploaded_file() parse_ini_file() pathinfo() pclose() popen() readfile() readlink() realpath() rename() rewind() rmdir() set_file_buffer() stat() symlink() tempnam() tmpfile() touch() umask() unlink()

Checks whether a file is executable Checks whether a file is a regular file Checks whether a file is a link Checks whether a file is readable Checks whether a file was uploaded via HTTP POST Checks whether a file is writeable Alias of is_writable() Creates a hard link Returns information about a hard link Returns information about a file or symbolic link Creates a directory Moves an uploaded file to a new location Parses a configuration file Returns information about a file path Closes a pipe opened by popen() Opens a pipe Reads a file and writes it to the output buffer Returns the target of a symbolic link Returns the absolute pathname Renames a file or directory Rewinds a file pointer Removes an empty directory Sets the buffer size of an open file Returns information about a file Creates a symbolic link Creates a unique temporary file Creates a unique temporary file Sets access and modification time of a file Changes file permissions for files Deletes a file

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PHP Filesystem Constants PHP: indicates the earliest version of PHP that supports the constant. Constant

Description

PHP

GLOB_BRACE GLOB_ONLYDIR GLOB_MARK GLOB_NOSORT GLOB_NOCHECK GLOB_NOESCAPE PATHINFO_DIRNAME PATHINFO_BASENAME

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PATHINFO_EXTENSION FILE_USE_INCLUDE_PATH FILE_APPEND FILE_IGNORE_NEW_LINES FILE_SKIP_EMPTY_LINES PHP Filter Functions PHP Filter Introduction This PHP filters is used to validate and filter data coming from insecure sources, like user input. Installation The filter functions are part of the PHP core. There is no installation needed to use these functions. PHP Filter Functions PHP: indicates the earliest version of PHP that supports the function. Function

Description

PHP

filter_has_var()

Checks if a variable of a specified input type exist

5

filter_id()

Returns the ID number of a specified filter

5

filter_input()

Get input from outside the script and filter it

5

filter_input_array()

5

filter_list()

Get multiple inputs from outside the script and filters them Returns an array of all supported filters

filter_var_array()

Get multiple variables and filter them

5

filter_var()

Get a variable and filter it

5

5

PHP Filters ID Name

Description

FILTER_CALLBACK

Call a user-defined function to filter data

FILTER_SANITIZE_STRING

Strip tags, optionally strip or encode special characters Alias of "string" filter

FILTER_SANITIZE_STRIPPED FILTER_SANITIZE_ENCODED FILTER_SANITIZE_SPECIAL_CHARS FILTER_SANITIZE_EMAIL FILTER_SANITIZE_URL FILTER_SANITIZE_NUMBER_INT FILTER_SANITIZE_NUMBER_FLOAT FILTER_SANITIZE_MAGIC_QUOTES FILTER_UNSAFE_RAW FILTER_VALIDATE_INT

URL-encode string, optionally strip or encode special characters HTML-escape '"<>& and characters with ASCII value less than 32 Remove all characters, except letters, digits and ! #$%&'*+-/=?^_`{|}~@.[] Remove all characters, except letters, digits and $_.+!*'(),{}|\\^~[]`<>#%";/?:@&= Remove all characters, except digits and +Remove all characters, except digits, +- and optionally .,eE Apply addslashes() Do nothing, optionally strip or encode special characters Validate value as integer, optionally from the specified range

50

FILTER_VALIDATE_BOOLEAN

Return TRUE for "1", "true", "on" and "yes", FALSE for "0", "false", "off", "no", and "", NULL otherwise Validate value as float

FILTER_VALIDATE_FLOAT FILTER_VALIDATE_REGEXP

Validate value against regexp, a Perl-compatible regular expression Validate value as URL, optionally with required components Validate value as e-mail

FILTER_VALIDATE_URL FILTER_VALIDATE_EMAIL FILTER_VALIDATE_IP

Validate value as IP address, optionally only IPv4 or IPv6 or not from private or reserved ranges

PHP FTP Functions PHP FTP Introduction The FTP functions give client access to file servers through the File Transfer Protocol (FTP). The FTP functions are used to open, login and close connections, as well as upload, download, rename, delete, and get information on files from file servers. Not all of the FTP functions will work with every server or return the same results. The FTP functions became available with PHP 3. These functions are meant for detailed access to an FTP server. If you only wish to read from or write to a file on an FTP server, consider using the ftp:// wrapper with the Filesystem functions. Installation The windows version of PHP has built-in support for the FTP extension. So, the FTP functions will work automatically. However, if you are running the Linux version of PHP, you will have to compile PHP with --enable-ftp (PHP 4+) or --with-ftp (PHP 3) to get the FTP functions to work. PHP FTP Functions PHP: indicates the earliest version of PHP that supports the function. Function

Description

PHP

ftp_alloc()

Allocates space for a file to be uploaded to the FTP server

5

ftp_cdup()

3

ftp_chdir()

Changes the current directory to the parent directory on the FTP server Changes the current directory on the FTP server

ftp_chmod()

Sets permissions on a file via FTP

5

ftp_close()

Closes an FTP connection

4

ftp_connect()

Opens an FTP connection

3

ftp_delete()

Deletes a file on the FTP server

3

ftp_exec()

Executes a program/command on the FTP server

4

ftp_fget()

Downloads a file from the FTP server and saves it to an open file

3

ftp_fput()

Uploads from an open file and saves it to a file on the FTP server

3

ftp_get_option()

Returns runtime behaviors of the FTP connection

4

ftp_get()

Downloads a file from the FTP server

3

ftp_login()

Logs on to an FTP connection

3

ftp_mdtm()

Returns the last modified time of a specified file

3

ftp_mkdir() ftp_nb_continue() ftp_nb_fget()

Creates a new directory on the FTP server Continues retrieving/sending a file (non-blocking) Downloads a file from the FTP server and saves it to an open file (non-blocking) Uploads from an open file and saves it to a file on the FTP server

3 4 4

ftp_nb_fput()

3

4

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ftp_nb_get() ftp_nb_put() ftp_nlist() ftp_pasv() ftp_put() ftp_pwd() ftp_quit() ftp_raw() ftp_rawlist() ftp_rename() ftp_rmdir() ftp_set_option() ftp_site() ftp_size() ftp_ssl_connect() ftp_systype()

(non-blocking) Downloads a file from the FTP server (non-blocking) Uploads a file to the FTP server (non-blocking) Lists the files in a specified directory on the FTP server Turns passive mode on or off Uploads a file to the FTP server Returns the current directory name Alias of ftp_close() Sends a raw command to the FTP server Returns a detailed list of files in the specified directory Renames a file or directory on the FTP server Removes a directory on the FTP server Sets runtime options for the FTP connection Sends a SITE command to the server Returns the size of the specified file Opens a secure SSL-FTP connection Returns the system type identifier of the FTP server

PHP FTP Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description FTP_ASCII FTP_TEXT FTP_BINARY FTP_IMAGE FTP_TIMEOUT_SEC FTP_AUTOSEEK FTP_AUTORESUME FTP_FAILED FTP_FINISHED FTP_MOREDATA

Determine resume position and start position for get and put requests automatically Asynchronous transfer has failed Asynchronous transfer has finished Asynchronous transfer is still active

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PHP 3 3 3 3 3 4 4 4 4 4

PHP HTTP Functions The HTTP functions let you manipulate information sent to the browser by the Web server, before any other output has been sent. Installation The directory functions are part of the PHP core. There is no installation needed to use these functions. PHP HTTP Functions PHP: indicates the earliest version of PHP that supports the function. Function

Description

PHP

header()

Sends a raw HTTP header to a client

3

headers_list()

Returns a list of response headers sent (or ready to send)

5

headers_sent()

Checks if / where the HTTP headers have been sent

3

setcookie()

Sends an HTTP cookie to a client

3

setrawcookie()

Sends an HTTP cookie without URL encoding the cookie value

5

PHP HTTP Constants None.

52

PHP libxml Functions PHP libxml Introduction The libxml functions and constants are used together with SimpleXML, XSLT and DOM functions. Installation These functions require the libxml package. Download at xmlsoft.org Function

Description

PHP

libxml_clear_errors()

Clear libxml error buffer

5

libxml_get_errors()

Retrieve array of errors

5

libxml_get_last_error()

Retrieve last error from libxml

5

libxml_set_streams_context()

Set the streams context for the next libxml document load or write Disable libxml errors and allow user to fetch error information as needed

5

libxml_use_internal_errors()

5

PHP libxml Constants Function LIBXML_COMPACT LIBXML_DTDATTR LIBXML_DTDLOAD LIBXML_DTDVALID LIBXML_NOBLANKS LIBXML_NOCDATA LIBXML_NOEMPTYTAG LIBXML_NOENT LIBXML_NOERROR LIBXML_NONET LIBXML_NOWARNING LIBXML_NOXMLDECL LIBXML_NSCLEAN LIBXML_XINCLUDE LIBXML_ERR_ERROR LIBXML_ERR_FATAL LIBXML_ERR_NONE LIBXML_ERR_WARNING LIBXML_VERSION LIBXML_DOTTED_VERSION

Description Set small nodes allocation optimization. This may improve the application performance Set default DTD attributes Load external subset Validate with the DTD Remove blank nodes Set CDATA as text nodes Change empty tags (e.g.
to

), only available in the DOMDocument->save() and DOMDocument->saveXML() functions Substitute entities Do not show error reports Stop network access while loading documents Do not show warning reports Drop the XML declaration when saving a document Remove excess namespace declarations Use XInclude substitution Get recoverable errors Get fatal errors Get no errors Get simple warnings Get libxml version (e.g. 20605 or 20617) Get dotted libxml version (e.g. 2.6.5 or 2.6.17)

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PHP Mail Functions PHP Mail Introduction The mail() function allows you to send emails directly from a script. Requirements For the mail functions to be available, PHP requires an installed and working email system. The program to be used is defined by the configuration settings in the php.ini file. Installation The mail functions are part of the PHP core. There is no installation needed to use these functions. Runtime Configuration The behavior of the mail functions is affected by settings in the php.ini file.

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Mail configuration options:

Name

Default

Description

Changeable

SMTP

"localhost"

Windows only: The DNS name or IP address of the SMTP server

PHP_INI_ALL

smtp_port

"25"

Windows only: The SMTP port number. Available since PHP 4.3

PHP_INI_ALL

sendmail_from

NULL

PHP_INI_ALL

sendmail_path

NULL

Windows only: Specifies the "from" address to be used in email sent from PHP Unix systems only: Specifies where the sendmail program can be found (usually /usr/sbin/sendmail or /usr/lib/sendmail)

PHP_INI_SYSTEM

PHP Mail Functions PHP: indicates the earliest version of PHP that supports the function. Function

Description

PHP

ezmlm_hash()

Calculates the hash value needed by the EZMLM mailing list system

3

mail()

Allows you to send emails directly from a script

3

PHP Mail Constants None.

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PHP Zip File Constants NONE PHP Include File Server Side Includes (SSI) are used to create functions, headers, footers, or elements that will be reused on multiple pages.

55

Server Side Includes You can insert the content of a file into a PHP file before the server executes it, with the include() or require() function. The two functions are identical in every way, except how they handle errors. The include() function generates a warning (but the script will continue execution) while the require() function generates a fatal error (and the script execution will stop after the error). These two functions are used to create functions, headers, footers, or elements that can be reused on multiple pages. This can save the developer a considerable amount of time. This means that you can create a standard header or menu file that you want all your web pages to include. When the header needs to be updated, you can only update this one include file, or when you add a new page to your site, you can simply change the menu file (instead of updating the links on all web pages). The include() Function The include() function takes all the text in a specified file and copies it into the file that uses the include function. Example 1 Assume that you have a standard header file, called "header.php". To include the header file in a page, use the include() function, like this:

Welcome to my home page

Some text

Example 2 Now, let's assume we have a standard menu file that should be used on all pages (include files usually have a ".php" extension). Look at the "menu.php" file below: Home | About Us | Contact Us The three files, "default.php", "about.php", and "contact.php" should all include the "menu.php" file. Here is the code in "default.php":

Welcome to my home page

Some text

If you look at the source code of the "default.php" in a browser, it will look something like this: Home | About Us | Contact Us

Welcome to my home page

Some text

And, of course, we would have to do the same thing for "about.php" and "contact.php". By using include files, you simply have to update the text in the "menu.php" file if you decide to rename or change the order of the links or add another web page to the site. The require() Function The require() function is identical to include(), except that it handles errors differently. The include() function generates a warning (but the script will continue execution) while the require() function generates a fatal error (and the script execution will stop after the error). If you include a file with the include() function and an error occurs, you might get an error message like the one below.

56

PHP code: Error message: Warning: include(wrongFile.php) [function.include]: failed to open stream: No such file or directory in C:\home\website\test.php on line 5 Warning: include() [function.include]: Failed opening 'wrongFile.php' for inclusion (include_path='.;C:\php5\pear') in C:\home\website\test.php on line 5 Hello World! Notice that the echo statement is still executed! This is because a Warning does not stop the script execution. Now, let's run the same example with the require() function. PHP code: Error message: Warning: require(wrongFile.php) [function.require]: failed to open stream: No such file or directory in C:\home\website\test.php on line 5 Fatal error: require() [function.require]: Failed opening required 'wrongFile.php' (include_path='.;C:\php5\pear') in C:\home\website\test.php on line 5 The echo statement was not executed because the script execution stopped after the fatal error. It is recommended to use the require() function instead of include(), because scripts should not continue executing if files are missing or misnamed. PHP File Handling The fopen() function is used to open files in PHP. Opening a File The fopen() function is used to open files in PHP. The first parameter of this function contains the name of the file to be opened and the second parameter specifies in which mode the file should be opened:

57

The file may be opened in one of the following modes: Modes Description r Read only. Starts at the beginning of the file r+ Read/Write. Starts at the beginning of the file w Write only. Opens and clears the contents of file; or creates a new file if it doesn't exist w+ Read/Write. Opens and clears the contents of file; or creates a new file if it doesn't exist a Append. Opens and writes to the end of the file or creates a new file if it doesn't exist a+ Read/Append. Preserves file content by writing to the end of the file x Write only. Creates a new file. Returns FALSE and an error if file already exists x+ Read/Write. Creates a new file. Returns FALSE and an error if file already exists Note: If the fopen() function is unable to open the specified file, it returns 0 (false). Example The following example generates a message if the fopen() function is unable to open the specified file: Closing a File The fclose() function is used to close an open file:

Check End-of-file The feof() function checks if the "end-of-file" (EOF) has been reached. The feof() function is useful for looping through data of unknown length. Note: You cannot read from files opened in w, a, and x mode! if (feof($file)) echo "End of file";

Reading a File Line by Line The fgets() function is used to read a single line from a file. Note: After a call to this function the file pointer has moved to the next line. Example The example below reads a file line by line, until the end of file is reached: "; } fclose($file); ?>

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Reading a File Character by Character The fgetc() function is used to read a single character from a file. Note: After a call to this function the file pointer moves to the next character. Example The example below reads a file character by character, until the end of file is reached: PHP Filesystem Functions PHP Filesystem Introduction The filesystem functions allow you to access and manipulate the filesystem. Installation The filesystem functions are part of the PHP core. There is no installation needed to use these functions. Runtime Configuration The behavior of the filesystem functions is affected by settings in php.ini. Filesystem configuration options: Name Default Description allow_url_fopen "1" Allows fopen()-type functions to work with URLs (available since PHP 4.0.4) user_agent NULL Defines the user agent for PHP to send (available since PHP 4.3) default_socket_timeout "60" Sets the default timeout, in seconds, for socket based streams (available since PHP 4.3) from "" Defines the anonymous FTP password (your email address) auto_detect_line_endings "0" When set to "1", PHP will examine the data read by fgets() and file() to see if it is using Unix, MS-Dos or Mac line-ending characters (available since PHP 4.3)

Changeable PHP_INI_SYSTEM PHP_INI_ALL PHP_INI_ALL

PHP_INI_ALL PHP_INI_ALL

Unix / Windows Compatibility When specifying a path on Unix platforms, the forward slash (/) is used as directory separator. However, on Windows platforms, both forward slash (/) and backslash (\) can be used. PHP Filesystem Functions PHP: indicates the earliest version of PHP that supports the function. Function Description basename() Returns the filename component of a path chgrp() Changes the file group chmod() Changes the file mode chown() Changes the file owner clearstatcache() Clears the file status cache copy() Copies a file delete() See unlink() or unset() dirname() Returns the directory name component of a path disk_free_space() Returns the free space of a directory

PHP 3 3 3 3 3 3 3 4

59

disk_total_space() diskfreespace() fclose() feof() fflush() fgetc() fgetcsv() fgets() fgetss() file() file_exists() file_get_contents() file_put_contents fileatime() filectime() filegroup() fileinode() filemtime() fileowner() fileperms() filesize() filetype() flock() fnmatch() fopen() fpassthru() fputcsv() fputs() fread() fscanf() fseek() fstat() ftell() ftruncate() fwrite() glob() is_dir() is_executable() is_file() is_link() is_readable() is_uploaded_file() is_writable() is_writeable() link() linkinfo() lstat() mkdir()

Returns the total size of a directory Alias of disk_free_space() Closes an open file Tests for end-of-file on an open file Flushes buffered output to an open file Returns a character from an open file Parses a line from an open file, checking for CSV fields Returns a line from an open file Returns a line, with HTML and PHP tags removed, from an open file Reads a file into an array Checks whether or not a file or directory exists Reads a file into a string Writes a string to a file Returns the last access time of a file Returns the last change time of a file Returns the group ID of a file Returns the inode number of a file Returns the last modification time of a file Returns the user ID (owner) of a file Returns the permissions of a file Returns the file size Returns the file type Locks or releases a file Matches a filename or string against a specified pattern Opens a file or URL Reads from an open file, until EOF, and writes the result to the output buffer Formats a line as CSV and writes it to an open file Alias of fwrite() Reads from an open file Parses input from an open file according to a specified format Seeks in an open file Returns information about an open file Returns the current position in an open file Truncates an open file to a specified length Writes to an open file Returns an array of filenames / directories matching a specified pattern Checks whether a file is a directory Checks whether a file is executable Checks whether a file is a regular file Checks whether a file is a link Checks whether a file is readable Checks whether a file was uploaded via HTTP POST Checks whether a file is writeable Alias of is_writable() Creates a hard link Returns information about a hard link Returns information about a file or symbolic link Creates a directory

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60

move_uploaded_file() parse_ini_file() pathinfo() pclose() popen() readfile() readlink() realpath() rename() rewind() rmdir() set_file_buffer() stat() symlink() tempnam() tmpfile() touch() umask() unlink()

Moves an uploaded file to a new location Parses a configuration file Returns information about a file path Closes a pipe opened by popen() Opens a pipe Reads a file and writes it to the output buffer Returns the target of a symbolic link Returns the absolute pathname Renames a file or directory Rewinds a file pointer Removes an empty directory Sets the buffer size of an open file Returns information about a file Creates a symbolic link Creates a unique temporary file Creates a unique temporary file Sets access and modification time of a file Changes file permissions for files Deletes a file

PHP Filesystem Constants PHP: indicates the earliest version of PHP that supports the constant. Constant Description GLOB_BRACE GLOB_ONLYDIR GLOB_MARK GLOB_NOSORT GLOB_NOCHECK GLOB_NOESCAPE PATHINFO_DIRNAME PATHINFO_BASENAME PATHINFO_EXTENSION FILE_USE_INCLUDE_PATH FILE_APPEND FILE_IGNORE_NEW_LINES FILE_SKIP_EMPTY_LINES

4 4 4 3 3 3 3 4 3 3 3 3 3 3 3 3 3 3 3

PHP

PHP MySQL Connect to a Database The free MySQL database is very often used with PHP. Create a Connection to a MySQL Database Before you can access data in a database, you must create a connection to the database. In PHP, this is done with the mysql_connect() function. Syntax mysql_connect(servername,username,password); Parameter servername username

Description Optional. Specifies the server to connect to. Default value is "localhost:3306" Optional. Specifies the username to log in with. Default value is the name of the user that owns the server process

61

password Optional. Specifies the password to log in with. Default is "" Note: There are more available parameters, but the ones listed above are the most important. Visit our full PHP MySQL Reference for more details.

Example In the following example we store the connection in a variable ($con) for later use in the script. The "die" part will be executed if the connection fails:

Closing a Connection The connection will be closed automatically when the script ends. To close the connection before, use the mysql_close() function: PHP MySQL Create Database and Tables A database holds one or multiple tables. Create a Database The CREATE DATABASE statement is used to create a database in MySQL. Syntax CREATE DATABASE database_name To learn more about SQL, please visit our SQL tutorial. To get PHP to execute the statement above we must use the mysql_query() function. This function is used to send a query or command to a MySQL connection. Example The following example creates a database called "my_db":
62

} mysql_close($con); ?>

Create a Table The CREATE TABLE statement is used to create a table in MySQL. Syntax CREATE TABLE table_name ( column_name1 data_type, column_name2 data_type, column_name3 data_type, .... ) To learn more about SQL, please visit our SQL tutorial. We must add the CREATE TABLE statement to the mysql_query() function to execute the command. Example The following example creates a table named "Persons", with three columns. The column names will be "FirstName", "LastName" and "Age": Important: A database must be selected before a table can be created. The database is selected with the mysql_select_db() function. Note: When you create a database field of type varchar, you must specify the maximum length of the field, e.g. varchar(15). The data type specifies what type of data the column can hold. For a complete reference of all the data types available in MySQL, go to our complete Data Types reference. Primary Keys and Auto Increment Fields Each table should have a primary key field.

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A primary key is used to uniquely identify the rows in a table. Each primary key value must be unique within the table. Furthermore, the primary key field cannot be null because the database engine requires a value to locate the record. The following example sets the personID field as the primary key field. The primary key field is often an ID number, and is often used with the AUTO_INCREMENT setting. AUTO_INCREMENT automatically increases the value of the field by 1 each time a new record is added. To ensure that the primary key field cannot be null, we must add the NOT NULL setting to the field. Example $sql = "CREATE TABLE Persons ( personID int NOT NULL AUTO_INCREMENT, PRIMARY KEY(personID), FirstName varchar(15), LastName varchar(15), Age int )"; mysql_query($sql,$con); PHP MySQL Insert Into The INSERT INTO statement is used to insert new records in a table. Insert Data Into a Database Table The INSERT INTO statement is used to add new records to a database table. Syntax It is possible to write the INSERT INTO statement in two forms. The first form doesn't specify the column names where the data will be inserted, only their values: INSERT INTO table_name VALUES (value1, value2, value3,...) The second form specifies both the column names and the values to be inserted: INSERT INTO table_name (column1, column2, column3,...) VALUES (value1, value2, value3,...) To learn more about SQL, please visit our SQL tutorial. To get PHP to execute the statements above we must use the mysql_query() function. This function is used to send a query or command to a MySQL connection. Example In the previous chapter we created a table named "Persons", with three columns; "Firstname", "Lastname" and "Age". We will use the same table in this example. The following example adds two new records to the "Persons" table: Insert Data From a Form Into a Database Now we will create an HTML form that can be used to add new records to the "Persons" table. Here is the HTML form:

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Firstname: Lastname: Age:

When a user clicks the submit button in the HTML form in the example above, the form data is sent to "insert.php". The "insert.php" file connects to a database, and retrieves the values from the form with the PHP $_POST variables. Then, the mysql_query() function executes the INSERT INTO statement, and a new record will be added to the "Persons" table. Here is the "insert.php" page: PHP MySQL Select The SELECT statement is used to select data from a database. Select Data From a Database Table The SELECT statement is used to select data from a database. Syntax SELECT column_name(s) FROM table_name To learn more about SQL, please visit our SQL tutorial. To get PHP to execute the statement above we must use the mysql_query() function. This function is used to send a query or command to a MySQL connection. Example The following example selects all the data stored in the "Persons" table (The * character selects all the data in the table): ";

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} mysql_close($con); ?> The example above stores the data returned by the mysql_query() function in the $result variable. Next, we use the mysql_fetch_array() function to return the first row from the recordset as an array. Each call to mysql_fetch_array() returns the next row in the recordset. The while loop loops through all the records in the recordset. To print the value of each row, we use the PHP $row variable ($row['FirstName'] and $row['LastName']). The output of the code above will be: Peter Griffin Glenn Quagmire

Display the Result in an HTML Table The following example selects the same data as the example above, but will display the data in an HTML table: Firstname Lastname "; while($row = mysql_fetch_array($result)) { echo ""; echo "" . $row['FirstName'] . ""; echo "" . $row['LastName'] . ""; echo ""; } echo ""; mysql_close($con); ?> The output of the code above will be: Firstname Lastname Glenn

Quagmire

Peter

Griffin

PHP MySQL The Where Clause The WHERE clause is used to filter records. The WHERE clause The WHERE clause is used to extract only those records that fulfill a specified criterion. Syntax SELECT column_name(s) FROM table_name WHERE column_name operator value To get PHP to execute the statement above we must use the mysql_query() function. This function is used to send a query or command to a MySQL connection.

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Example The following example selects all rows from the "Persons" table where "FirstName='Peter': "; } ?> The output of the code above will be: Peter Griffin PHP MySQL Order By Keyword The ORDER BY keyword is used to sort the data in a recordset. The ORDER BY Keyword The ORDER BY keyword is used to sort the data in a recordset. The ORDER BY keyword sort the records in ascending order by default. If you want to sort the records in a descending order, you can use the DESC keyword. Syntax SELECT column_name(s) FROM table_name ORDER BY column_name(s) ASC|DESC To learn more about SQL, please visit our SQL tutorial. Example The following example selects all the data stored in the "Persons" table, and sorts the result by the "Age" column: "; } mysql_close($con); ?>

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The output of the code above will be: Glenn Quagmire 33 Peter Griffin 35

Order by Two Columns It is also possible to order by more than one column. When ordering by more than one column, the second column is only used if the values in the first column are equal: SELECT column_name(s) FROM table_name ORDER BY column1, column2 PHP MySQL Update The UPDATE statement is used to modify data in a table. Update Data In a Database The UPDATE statement is used to update existing records in a table. Syntax UPDATE table_name SET column1=value, column2=value2,... WHERE some_column=some_value Note: Notice the WHERE clause in the UPDATE syntax. The WHERE clause specifies which record or records that should be updated. If you omit the WHERE clause, all records will be updated! To learn more about SQL, please visit our SQL tutorial. To get PHP to execute the statement above we must use the mysql_query() function. This function is used to send a query or command to a MySQL connection. Example Earlier in the tutorial we created a table named "Persons". Here is how it looks: FirstName LastName Peter Griffin Glenn Quagmire The following example updates some data in the "Persons" table:

Age 35 33

After the update, the "Persons" table will look like this: FirstName LastName Peter Griffin Glenn Quagmire

Age 36 33

PHP MySQL Delete The DELETE statement is used to delete records in a table. Delete Data In a Database The DELETE FROM statement is used to delete records from a database table. Syntax DELETE FROM table_name

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WHERE some_column = some_value Note: Notice the WHERE clause in the DELETE syntax. The WHERE clause specifies which record or records that should be deleted. If you omit the WHERE clause, all records will be deleted! To learn more about SQL, please visit our SQL tutorial. To get PHP to execute the statement above we must use the mysql_query() function. This function is used to send a query or command to a MySQL connection. Example Look at the following "Persons" table: FirstName LastName Age Peter Griffin 35 Glenn Quagmire 33 The following example deletes all the records in the "Persons" table where LastName='Griffin': After the deletion, the table will look like this: FirstName LastName Glenn Quagmire

Age 33

PHP Database ODBC ODBC is an Application Programming Interface (API) that allows you to connect to a data source (e.g. an MS Access database). Create an ODBC Connection With an ODBC connection, you can connect to any database, on any computer in your network, as long as an ODBC connection is available. Here is how to create an ODBC connection to a MS Access Database: Open the Administrative Tools icon in your Control Panel. Double-click on the Data Sources (ODBC) icon inside. Choose the System DSN tab. Click on Add in the System DSN tab. Select the Microsoft Access Driver. Click Finish. In the next screen, click Select to locate the database. Give the database a Data Source Name (DSN). Click OK. Note that this configuration has to be done on the computer where your web site is located. If you are running Internet Information Server (IIS) on your own computer, the instructions above will work, but if your web site is located on a remote server, you have to have physical access to that server, or ask your web host to to set up a DSN for you to use. Connecting to an ODBC The odbc_connect() function is used to connect to an ODBC data source. The function takes four parameters: the data source name, username, password, and an optional cursor type. The odbc_exec() function is used to execute an SQL statement. Example The following example creates a connection to a DSN called northwind, with no username and no password. It then creates an SQL and executes it: $conn=odbc_connect('northwind','','');

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$sql="SELECT * FROM customers"; $rs=odbc_exec($conn,$sql);

Retrieving Records The odbc_fetch_row() function is used to return records from the result-set. This function returns true if it is able to return rows, otherwise false. The function takes two parameters: the ODBC result identifier and an optional row number: odbc_fetch_row($rs) Retrieving Fields from a Record The odbc_result() function is used to read fields from a record. This function takes two parameters: the ODBC result identifier and a field number or name. The code line below returns the value of the first field from the record: $compname=odbc_result($rs,1); The code line below returns the value of a field called "CompanyName": $compname=odbc_result($rs,"CompanyName"); Closing an ODBC Connection The odbc_close() function is used to close an ODBC connection. odbc_close($conn);

An ODBC Example The following example shows how to first create a database connection, then a result-set, and then display the data in an HTML table. "; echo "Companyname"; echo "Contactname"; while (odbc_fetch_row($rs)) { $compname=odbc_result($rs,"CompanyName"); $conname=odbc_result($rs,"ContactName"); echo "$compname"; echo "$conname"; } odbc_close($conn); echo ""; ?> PHP XML Expat Parser The built-in Expat parser makes it possible to process XML documents in PHP. What is XML? XML is used to describe data and to focus on what data is. An XML file describes the structure of the data.

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In XML, no tags are predefined. You must define your own tags. If you want to learn more about XML, please visit our XML tutorial. What is Expat? To read and update - create and manipulate - an XML document, you will need an XML parser. There are two basic types of XML parsers: Tree-based parser: This parser transforms an XML document into a tree structure. It analyzes the whole document, and provides access to the tree elements. e.g. the Document Object Model (DOM) Event-based parser: Views an XML document as a series of events. When a specific event occurs, it calls a function to handle it The Expat parser is an event-based parser. Event-based parsers focus on the content of the XML documents, not their structure. Because of this, eventbased parsers can access data faster than tree-based parsers. Look at the following XML fraction: Jani An event-based parser reports the XML above as a series of three events: Start element: from Start CDATA section, value: Jani Close element: from The XML example above contains well-formed XML. However, the example is not valid XML, because there is no Document Type Definition (DTD) associated with it. However, this makes no difference when using the Expat parser. Expat is a non-validating parser, and ignores any DTDs. As an event-based, non-validating XML parser, Expat is fast and small, and a perfect match for PHP web applications. Note: XML documents must be well-formed or Expat will generate an error. Installation The XML Expat parser functions are part of the PHP core. There is no installation needed to use these functions. An XML File The XML file below will be used in our example: <note> Tove Jani Reminder Don't forget me this weekend! Initializing the XML Parser We want to initialize the XML parser in PHP, define some handlers for different XML events, and then parse the XML file. Example "; break; case "TO": echo "To: ";

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break; case "FROM": echo "From: "; break; case "HEADING": echo "Heading: "; break; case "BODY": echo "Message: "; } } //Function to use at the end of an element function stop($parser,$element_name) { echo "
"; } //Function to use when finding character data function char($parser,$data) { echo $data; } //Specify element handler xml_set_element_handler($parser,"start","stop"); //Specify data handler xml_set_character_data_handler($parser,"char"); //Open XML file $fp=fopen("test.xml","r"); //Read data while ($data=fread($fp,4096)) { xml_parse($parser,$data,feof($fp)) or die (sprintf("XML Error: %s at line %d", xml_error_string(xml_get_error_code($parser)), xml_get_current_line_number($parser))); } //Free the XML parser xml_parser_free($parser); ?> The output of the code above will be: -- Note -To: Tove From: Jani Heading: Reminder Message: Don't forget me this weekend! How it works: Initialize the XML parser with the xml_parser_create() function Create functions to use with the different event handlers Add the xml_set_element_handler() function to specify which function will be executed when the parser encounters the opening and closing tags Add the xml_set_character_data_handler() function to specify which function will execute when the parser encounters character data Parse the file "test.xml" with the xml_parse() function In case of an error, add xml_error_string() function to convert an XML error to a textual description Call the xml_parser_free() function to release the memory allocated with the xml_parser_create() function PHP XML DOM The built-in DOM parser makes it possible to process XML documents in PHP. What is DOM? The W3C DOM provides a standard set of objects for HTML and XML documents, and a standard interface for accessing and manipulating them.

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The W3C DOM is separated into different parts (Core, XML, and HTML) and different levels (DOM Level 1/2/3): * Core DOM - defines a standard set of objects for any structured document * XML DOM - defines a standard set of objects for XML documents * HTML DOM - defines a standard set of objects for HTML documents If you want to learn more about the XML DOM, please visit our XML DOM tutorial. XML Parsing To read and update - create and manipulate - an XML document, you will need an XML parser. There are two basic types of XML parsers: Tree-based parser: This parser transforms an XML document into a tree structure. It analyzes the whole document, and provides access to the tree elements Event-based parser: Views an XML document as a series of events. When a specific event occurs, it calls a function to handle it The DOM parser is an tree-based parser. Look at the following XML document fraction: Jani The XML DOM sees the XML above as a tree structure: Level 1: XML Document Level 2: Root element: Level 3: Text element: "Jani" Installation The DOM XML parser functions are part of the PHP core. There is no installation needed to use these functions. An XML File The XML file below will be used in our example: <note> Tove Jani Reminder Don't forget me this weekend! Load and Output XML We want to initialize the XML parser, load the xml, and output it: Example load("note.xml"); print $xmlDoc->saveXML(); ?> The output of the code above will be: Tove Jani Reminder Don't forget me this weekend! If you select "View source" in the browser window, you will see the following HTML: <note> Tove Jani Reminder Don't forget me this weekend! The example above creates a DOMDocument-Object and loads the XML from "note.xml" into it. Then the saveXML() function to puts the internal XML document into a string, so we can output it.

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Looping through XML We want to initialize the XML parser, load the XML, and loop through all elements of the <note> element: Example load("note.xml"); $x = $xmlDoc->documentElement; foreach ($x->childNodes AS $item) { print $item->nodeName . " = " . $item->nodeValue . "
"; } ?> The output of the code above will be: #text = to = Tove #text = from = Jani #text = heading = Reminder #text = body = Don't forget me this weekend! #text = In the example above you see that there are empty text nodes between each element. When XML generates, it often contains white-spaces between the nodes. The XML DOM parser treats these as ordinary elements, and if you are not aware of them, they sometimes cause problems. PHP SimpleXML SimpleXML handles the most common XML tasks and leaves the rest for other extensions. What is SimpleXML? SimpleXML is new in PHP 5. It is an easy way of getting an element's attributes and text, if you know the XML document's layout. Compared to DOM or the Expat parser, SimpleXML just takes a few lines of code to read text data from an element. SimpleXML converts the XML document into an object, like this: Elements - Are converted to single attributes of the SimpleXMLElement object. When there's more than one element on one level, they're placed inside an array Attributes - Are accessed using associative arrays, where an index corresponds to the attribute name Element Data - Text data from elements are converted to strings. If an element has more than one text node, they will be arranged in the order they are found SimpleXML is fast and easy to use when performing basic tasks like: Reading XML files Extracting data from XML strings Editing text nodes or attributes However, when dealing with advanced XML, like namespaces, you are better off using the Expat parser or the XML DOM. Installation As of PHP 5.0, the SimpleXML functions are part of the PHP core. There is no installation needed to use these functions. Using SimpleXML Below is an XML file: <note> Tove Jani Reminder Don't forget me this weekend! We want to output the element names and data from the XML file above. Here's what to do: Load the XML file

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Get the name of the first element Create a loop that will trigger on each child node, using the children() function Output the element name and data for each child node Example getName() . "
"; foreach($xml->children() as $child) { echo $child->getName() . ": " . $child . "
"; } ?> The output of the code above will be: note to: Tove from: Jani heading: Reminder body: Don't forget me this weekend! AJAX Introduction AJAX = Asynchronous JavaScript And XML AJAX is an acronym for Asynchronous JavaScript And XML. AJAX is not a new programming language, but simply a new technique for creating better, faster, and more interactive web applications. AJAX uses JavaScript to send and receive data between a web browser and a web server. The AJAX technique makes web pages more responsive by exchanging data with the web server behind the scenes, instead of reloading an entire web page each time a user makes a change. AJAX Is Based On Open Standards AJAX is based on the following open standards: JavaScript XML HTML CSS The open standards used in AJAX are well defined, and supported by all major browsers. AJAX applications are browser and platform independent. (Cross-Platform, Cross-Browser technology) AJAX Is About Better Internet Applications Web applications have many benefits over desktop applications: they can reach a larger audience they are easier to install and support they are easier to develop However, Internet applications are not always as "rich" and user-friendly as traditional desktop applications. With AJAX, Internet applications can be made richer (smaller, faster, and easier to use). You Can Start Using AJAX Today There is nothing new to learn. AJAX is based on open standards. These standards have been used by most developers for several years. Most existing web applications can be rewritten to use AJAX technology instead of traditional HTML forms. AJAX Uses XML And HTTP Requests A traditional web application will submit input (using an HTML form) to a web server. After the web server has processed the data, it will return a completely new web page to the user. Because the server returns a new web page each time the user submits input, traditional web applications often run slowly and tend to be less user friendly. With AJAX, web applications can send and retrieve data without reloading the whole web page. This is done by sending HTTP requests to the server (behind the scenes), and by modifying only parts of the web page using JavaScript when the server returns data. XML is commonly used as the format for receiving server data, although any format, including plain text, can be used. You will learn more about how this is done in the next chapters of this tutorial.

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PHP and AJAX There is no such thing as an AJAX server. AJAX is a technology that runs in your browser. It uses asynchronous data transfer (HTTP requests) between the browser and the web server, allowing web pages to request small bits of information from the server instead of whole pages. AJAX is a web browser technology independent of web server software. However, in this tutorial we will focus more on actual examples running on a PHP server, and less on how AJAX works. AJAX XMLHttpRequest The XMLHttpRequest object makes AJAX possible. The XMLHttpRequest The XMLHttpRequest object is the key to AJAX. It has been available ever since Internet Explorer 5.5 was released in July 2000, but not fully discovered before people started to talk about AJAX and Web 2.0 in 2005. Creating An XMLHttpRequest Object Different browsers use different methods to create an XMLHttpRequest object. Internet Explorer uses an ActiveXObject. Other browsers uses a built in JavaScript object called XMLHttpRequest. Here is the simplest code you can use to overcome this problem: var XMLHttp=null; if (window.XMLHttpRequest) { XMLHttp=new XMLHttpRequest(); } else if (window.ActiveXObject) { XMLHttp=new ActiveXObject("Microsoft.XMLHTTP"); } Example above explained: First create a variable XMLHttp to use as your XMLHttpRequest object. Set the value to null. Then test if the object window.XMLHttpRequest is available. This object is available in newer versions of Firefox, Mozilla, Opera, and Safari. If it's available, use it to create a new object: XMLHttp=new XMLHttpRequest() If it's not available, test if an object window.ActiveXObject is available. This object is available in Internet Explorer version 5.5 and later. If it is available, use it to create a new object: XMLHttp=new ActiveXObject() A Better Example? Some programmers will prefer to use the newest and fastest version of the XMLHttpRequest object. The example below tries to load Microsoft's latest version "Msxml2.XMLHTTP", available in Internet Explorer 6, before it falls back to "Microsoft.XMLHTTP", available in Internet Explorer 5.5 and later. function GetXmlHttpObject() { var xmlHttp=null; try { // Firefox, Opera 8.0+, Safari xmlHttp=new XMLHttpRequest(); } catch (e) { // Internet Explorer try { xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");

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} } return xmlHttp; }

Example above explained: First create a variable XMLHttp to use as your XMLHttpRequest object. Set the value to null. Try to create the object according to web standards (Mozilla, Opera and Safari):XMLHttp=new XMLHttpRequest() Try to create the object the Microsoft way, available in Internet Explorer 6 and later:XMLHttp=new ActiveXObject("Msxml2.XMLHTTP") If this catches an error, try the older (Internet Explorer 5.5) way: XMLHttp=new ActiveXObject("Microsoft.XMLHTTP") PHP and AJAX Suggest AJAX Suggest In the AJAX example below we will demonstrate how a web page can communicate with a web server online as a user enters data into a web form. Type a Name in the Box Below Top of Form First Name: Bottom of Form Suggestions: This example consists of three pages: a simple HTML form a JavaScript a PHP page The HTML Form This is the HTML page. It contains a simple HTML form and a link to a JavaScript: <script src="clienthint.js">

First Name:

Suggestions: <span id="txtHint">

Example Explained - The HTML Form As you can see, the HTML page above contains a simple HTML form with an input field called "txt1". The form works like this: An event is triggered when the user presses, and releases a key in the input field When the event is triggered, a function called showHint() is executed. Below the form is a <span> called "txtHint". This is used as a placeholder for the return data of the showHint() function. The JavaScript The JavaScript code is stored in "clienthint.js" and linked to the HTML document: var xmlHttp;

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function showHint(str) { if (str.length==0) { document.getElementById("txtHint").innerHTML=""; return; } xmlHttp=GetXmlHttpObject(); if (xmlHttp==null) { alert ("Browser does not support HTTP Request"); return; } var url="gethint.php"; url=url+"?q="+str; url=url+"&sid="+Math.random(); xmlHttp.onreadystatechange=stateChanged; xmlHttp.open("GET",url,true); xmlHttp.send(null); } function stateChanged() { if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") { document.getElementById("txtHint").innerHTML=xmlHttp.responseText; } } function GetXmlHttpObject() { var xmlHttp=null; try { // Firefox, Opera 8.0+, Safari xmlHttp=new XMLHttpRequest(); } catch (e) { // Internet Explorer try { xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); } } return xmlHttp; } Example Explained The showHint() Function This function executes every time a character is entered in the input field. If there is some input in the text field (str.length > 0) the function executes the following: Defines the url (filename) to send to the server Adds a parameter (q) to the url with the content of the input field Adds a random number to prevent the server from using a cached file Calls on the GetXmlHttpObject function to create an XMLHTTP object, and tells the object to execute a function called stateChanged when a change is triggered

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Opens the XMLHTTP object with the given url. Sends an HTTP request to the server If the input field is empty, the function simply clears the content of the txtHint placeholder. The stateChanged() Function This function executes every time the state of the XMLHTTP object changes. When the state changes to 4 (or to "complete"), the content of the txtHint placeholder is filled with the response text. The GetXmlHttpObject() Function AJAX applications can only run in web browsers with complete XML support. The code above called a function called GetXmlHttpObject(). The purpose of the function is to solve the problem of creating different XMLHTTP objects for different browsers. This is explained in the previous chapter. The PHP Page The server page called by the JavaScript code is a simple PHP file called "gethint.php". The code in the "gethint.php" checks an array of names and returns the corresponding names to the client: 0 if (strlen($q) > 0) { $hint=""; for($i=0; $i
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$hint=$a[$i]; } else { $hint=$hint." , ".$a[$i]; } } } } //Set output to "no suggestion" if no hint were found //or to the correct values if ($hint == "") { $response="no suggestion"; } else { $response=$hint; } //output the response echo $response; ?> If there is any text sent from the JavaScript (strlen($q) > 0) the following happens: Find a name matching the characters sent from the JavaScript If more than one name is found, include all names in the response string If no matching names were found, set response to "no suggestion" If one or more matching names were found, set response to these names The response is sent to the "txtHint" placeholder PHP and AJAX XML Example AJAX can be used for interactive communication with an XML file. AJAX XML Example In the AJAX example below we will demonstrate how a web page can fetch information from an XML file using AJAX technology. Select a CD in the Box Below Top of Form Select a CD: Bottom of Form CD info will be listed here. This example consists of four pages: a simple HTML form an XML file a JavaScript a PHP page The HTML Form The example above contains a simple HTML form and a link to a JavaScript: <script src="selectcd.js">

Select a CD:

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<select name="cds" onchange="showCD(this.value)"> Bob Dylan Bee Gees Cat Stevens

CD info will be listed here.

Example Explained As you can see it is just a simple HTML form with a simple drop down box called "cds". The paragraph below the form contains a div called "txtHint". The div is used as a placeholder for info retrieved from the web server. When the user selects data, a function called "showCD" is executed. The execution of the function is triggered by the "onchange" event. In other words: Each time the user changes the value in the drop down box, the function showCD is called. The XML File The XML file is "cd_catalog.xml". This document contains a CD collection. The JavaScript This is the JavaScript code stored in the file "selectcd.js": var xmlHttp; function showCD(str) { xmlHttp=GetXmlHttpObject(); if (xmlHttp==null) { alert ("Browser does not support HTTP Request"); return; } var url="getcd.php"; url=url+"?q="+str; url=url+"&sid="+Math.random(); xmlHttp.onreadystatechange=stateChanged; xmlHttp.open("GET",url,true); xmlHttp.send(null); } function stateChanged() { if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") { document.getElementById("txtHint").innerHTML=xmlHttp.responseText; } } function GetXmlHttpObject() { var xmlHttp=null; try { // Firefox, Opera 8.0+, Safari xmlHttp=new XMLHttpRequest(); } catch (e) { // Internet Explorer try {

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xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); } } return xmlHttp; } Example Explained The stateChanged() and GetXmlHttpObject functions are the same as in the last chapter, you can go to the previous page for an explanation of those The showCD() Function If an item in the drop down box is selected the function executes the following: Calls on the GetXmlHttpObject function to create an XMLHTTP object Defines the url (filename) to send to the server Adds a parameter (q) to the url with the content of the input field Adds a random number to prevent the server from using a cached file Call stateChanged when a change is triggered Opens the XMLHTTP object with the given url. Sends an HTTP request to the server The PHP Page The server paged called by the JavaScript, is a simple PHP file called "getcd.php". The page is written in PHP using the XML DOM to load the XML document "cd_catalog.xml". The code runs a query against the XML file and returns the result as HTML: load("cd_catalog.xml"); $x=$xmlDoc->getElementsByTagName('ARTIST'); for ($i=0; $i<=$x->length-1; $i++) { //Process only element nodes if ($x->item($i)->nodeType==1) { if ($x->item($i)->childNodes->item(0)->nodeValue == $q) { $y=($x->item($i)->parentNode); } } } $cd=($y->childNodes); for ($i=0;$i<$cd->length;$i++) { //Process only element nodes if ($cd->item($i)->nodeType==1) { echo($cd->item($i)->nodeName); echo(": "); echo($cd->item($i)->childNodes->item(0)->nodeValue); echo("
"); } } ?> Example Explained When the query is sent from the JavaScript to the PHP page the following happens: PHP creates an XML DOM object of the "cd_catalog.xml" file All "artist" elements (nodetypes = 1) are looped through to find a name matching the one sent from the JavaScript.

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The CD containing the correct artist is found The album information is output and sent to the "txtHint" placeholder PHP and AJAX MySQL Database Example AJAX can be used for interactive communication with a database. AJAX Database Example In the AJAX example below we will demonstrate how a web page can fetch information from a MySQL database using AJAX technology. Select a Name in the Box Below Top of Form Select a User: Bottom of Form User info will be listed here. This example consists of four elements: a MySQL database a simple HTML form a JavaScript a PHP page The Database The database we will be using in this example looks like this: id FirstName LastName Age Hometown 1 Peter Griffin 41 Quahog 2 Lois Griffin 40 Newport 3 Joseph Swanson 39 Quahog 4 Glenn Quagmire 41 Quahog

Job Brewery Piano Teacher Police Officer Pilot

The HTML Form The example above contains a simple HTML form and a link to a JavaScript: <script src="selectuser.js">

Select a User: <select name="users" onchange="showUser(this.value)"> Peter Griffin Lois Griffin Glenn Quagmire Joseph Swanson

User info will be listed here.

Example Explained - The HTML Form As you can see it is just a simple HTML form with a drop down box called "users" with names and the "id" from the database as option values. The paragraph below the form contains a div called "txtHint". The div is used as a placeholder for info retrieved from the web server. When the user selects data, a function called "showUser()" is executed. The execution of the function is triggered by the "onchange" event. In other words: Each time the user changes the value in the drop down box, the function showUser() is called. The JavaScript

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This is the JavaScript code stored in the file "selectuser.js": var xmlHttp; function showUser(str) { xmlHttp=GetXmlHttpObject(); if (xmlHttp==null) { alert ("Browser does not support HTTP Request"); return; } var url="getuser.php"; url=url+"?q="+str; url=url+"&sid="+Math.random(); xmlHttp.onreadystatechange=stateChanged; xmlHttp.open("GET",url,true); xmlHttp.send(null); } function stateChanged() { if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") { document.getElementById("txtHint").innerHTML=xmlHttp.responseText; } } function GetXmlHttpObject() { var xmlHttp=null; try { // Firefox, Opera 8.0+, Safari xmlHttp=new XMLHttpRequest(); } catch (e) { //Internet Explorer try { xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); } } return xmlHttp; } Example Explained The stateChanged() and GetXmlHttpObject functions are the same as in the PHP AJAX Suggest chapter, you can go to there for an explanation of those. The showUser() Function If an item in the drop down box is selected the function executes the following: Calls on the GetXmlHttpObject function to create an XMLHTTP object Defines the url (filename) to send to the server Adds a parameter (q) to the url with the content of the dropdown box Adds a random number to prevent the server from using a cached file Call stateChanged when a change is triggered Opens the XMLHTTP object with the given url. Sends an HTTP request to the server The PHP Page The server page called by the JavaScript, is a simple PHP file called "getuser.php".

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The page is written in PHP and uses a MySQL databse. The code runs a SQL query against a database and returns the result as an HTML table: Firstname Lastname Age Hometown Job "; while($row = mysql_fetch_array($result)) { echo ""; echo "" . $row['FirstName'] . ""; echo "" . $row['LastName'] . ""; echo "" . $row['Age'] . ""; echo "" . $row['Hometown'] . ""; echo "" . $row['Job'] . ""; echo ""; } echo ""; mysql_close($con); ?> Example Explained When the query is sent from the JavaScript to the PHP page the following happens: PHP opens a connection to a MySQL server The "user" with the specified name is found A table is created and the data is inserted and sent to the "txtHint" placeholder PHP and AJAX responseXML Example AJAX can be used to return database information as XML. AJAX Database as XML Example In the AJAX example below we will demonstrate how a web page can fetch information from a MySQL database, convert it to an XML document, and use it to display information in several different places. This example my seem a lot like the "PHP AJAX Database" example in the last chapter, however there is a big difference: in this example we get the data from the PHP page as XML using the responseXML function. Receiving the response as an XML document allows us to update this page several places, instead of just receiving a PHP output and displaying it. In this example we will update several <span> elements with the information we receive from the database. Select a Name in the Box Below Top of Form Select a User:

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Bottom of Form This example consists of four elements: a MySQL database a simple HTML form a JavaScript a PHP page The Database The database we will be using in this example looks like this: id FirstName LastName Age Hometown 1 Peter Griffin 41 Quahog 2 Lois Griffin 40 Newport 3 Joseph Swanson 39 Quahog 4 Glenn Quagmire 41 Quahog

Job Brewery Piano Teacher Police Officer Pilot

The HTML Form The example above contains a simple HTML form and a link to a JavaScript: <script src="responsexml.js">

Select a User: <select name="users" onchange="showUser(this.value)"> Peter Griffin Lois Griffin Glenn Quagmire Joseph Swanson

<span id="firstname">  <span id="lastname">

<span id="job">

<span id="age_text"> <span id="age"> <span id="hometown_text"> <span id="hometown">

Example Explained - The HTML Form The HTML form is a drop down box called "users" with names and the "id" from the database as option values. Below the form there are several different <span> elements which are used to as placeholders for the different values we will retrive. When the user selects data, a function called "showUser()" is executed. The execution of the function is triggered by the "onchange" event. In other words: Each time the user changes the value in the drop down box, the function showUser() is called and outputs the result in the specified <span> elements. The JavaScript This is the JavaScript code stored in the file "responsexml.js": var xmlHttp; function showUser(str) { xmlHttp=GetXmlHttpObject(); if (xmlHttp==null) {

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alert ("Browser does not support HTTP Request"); return; } var url="responsexml.php"; url=url+"?q="+str; url=url+"&sid="+Math.random(); xmlHttp.onreadystatechange=stateChanged; xmlHttp.open("GET",url,true); xmlHttp.send(null); } function stateChanged() { if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") { xmlDoc=xmlHttp.responseXML; document.getElementById("firstname").innerHTML= xmlDoc.getElementsByTagName("firstname")[0].childNodes[0].nodeValue; document.getElementById("lastname").innerHTML= xmlDoc.getElementsByTagName("lastname")[0].childNodes[0].nodeValue; document.getElementById("job").innerHTML= xmlDoc.getElementsByTagName("job")[0].childNodes[0].nodeValue; document.getElementById("age_text").innerHTML="Age: "; document.getElementById("age").innerHTML= xmlDoc.getElementsByTagName("age")[0].childNodes[0].nodeValue; document.getElementById("hometown_text").innerHTML="
From: "; document.getElementById("hometown").innerHTML= xmlDoc.getElementsByTagName("hometown")[0].childNodes[0].nodeValue; } } function GetXmlHttpObject() { var objXMLHttp=null; if (window.XMLHttpRequest) { objXMLHttp=new XMLHttpRequest(); } else if (window.ActiveXObject) { objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP"); } return objXMLHttp; } Example Explained The showUser() and GetXmlHttpObject functions are the same as in the PHP AJAX Database chapter, you can go to there for an explanation of those. The stateChanged() Function If an item in the drop down box is selected the function executes the following: Defines the "xmlDoc" variable as an xml document using the responseXML function Retrieves data from the xml documents and places them in the correct <span> elements The PHP Page The server page called by the JavaScript, is a simple PHP file called "responsexml.php". The page is written in PHP and uses a MySQL databse. The code runs a SQL query against a database and returns the result as an XML document:
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if (!$con) { die('Could not connect: ' . mysql_error()); } mysql_select_db("ajax_demo", $con); $sql="SELECT * FROM user WHERE id = ".$q.""; $result = mysql_query($sql); echo ' '; while($row = mysql_fetch_array($result)) { echo "" . $row['FirstName'] . ""; echo "" . $row['LastName'] . ""; echo "" . $row['Age'] . ""; echo "" . $row['Hometown'] . ""; echo "<job>" . $row['Job'] . ""; } echo ""; mysql_close($con); ?> Example Explained When the query is sent from the JavaScript to the PHP page the following happens: The content-type of the PHP document is set to be "text/xml" The PHP document is set to "no-cache" to prevent caching The $q variable is set to be the data sent from the html page PHP opens a connection to a MySQL server The "user" with the specified id is found The data is outputted as an xml document PHP and AJAX Live Search AJAX can be used for a more user friendly and interactive search. AJAX Live Search In the AJAX example below we will demonstrate a live search, where the server gets search results while the user types. Live search has many benefits compared to traditional searching: Matching results are shown as you type Results narrow as you continue typing If results become too narrow, remove characters to see a broader result Search for a W3Schools page in the Box Below Top of Form Bottom of Form This example consists of four pages: a simple HTML form a JavaScript a PHP page an XML document In this example the results are found in an XML document (links.xml). To make this example small and simple, only eight results are available. The HTML Form This is the HTML page. It contains a simple HTML form, style for the form and a link to a JavaScript: <script src="livesearch.js"> <style type="text/css"> #livesearch { margin:0px;

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width:194px; } #txt1 { margin:0px; }

Example Explained - The HTML Form As you can see, the HTML page above contains a simple HTML form with an input field called "txt1". The form works like this: An event is triggered when the user presses, and releases a key in the input field When the event is triggered, a function called showResult() is executed. Below the form is a

called "livesearch". This is used as a placeholder for the return data of the showResult() function. The JavaScript The JavaScript code is stored in "livesearch.js" and linked to the HTML document: var xmlHttp; function showResult(str) { if (str.length==0) { document.getElementById("livesearch"). innerHTML=""; document.getElementById("livesearch"). style.border="0px"; return; } xmlHttp=GetXmlHttpObject() if (xmlHttp==null) { alert ("Browser does not support HTTP Request"); return; } var url="livesearch.php"; url=url+"?q="+str; url=url+"&sid="+Math.random(); xmlHttp.onreadystatechange=stateChanged ; xmlHttp.open("GET",url,true); xmlHttp.send(null); } function stateChanged() { if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") { document.getElementById("livesearch"). innerHTML=xmlHttp.responseText; document.getElementById("livesearch"). style.border="1px solid #A5ACB2"; }

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} function GetXmlHttpObject() { var xmlHttp=null; try { // Firefox, Opera 8.0+, Safari xmlHttp=new XMLHttpRequest(); } catch (e) { // Internet Explorer try { xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); } } return xmlHttp; } Example Explained The GetXmlHttpObject function is the same as in the PHP AJAX Suggest chapter. The showResult() Function This function executes every time a character is entered in the input field. If there is no input in the text field (str.length == 0) the function sets the return field to empty and removes any border around it. However, if there is any input in the text field the function executes the following: Defines the url (filename) to send to the server Adds a parameter (q) to the url with the content of the input field Adds a random number to prevent the server from using a cached file Calls on the GetXmlHttpObject function to create an XMLHTTP object, and tells the object to execute a function called stateChanged when a change is triggered Opens the XMLHTTP object with the given url. Sends an HTTP request to the server The stateChanged() Function This function executes every time the state of the XMLHTTP object changes. When the state changes to 4 (or to "complete"), the content of the txtHint placeholder is filled with the response text, and a border is set around the return field. The PHP Page The server page called by the JavaScript code is a PHP file called "livesearch.php". The code in the "livesearch.php" checks the XML document "links.xml". This document contains titles and URL's of some pages on W3Schools.com. The code searches the XML file for titles matching the search string and returns the result as HTML: load("links.xml"); $x=$xmlDoc->getElementsByTagName('link'); //get the q parameter from URL $q=$_GET["q"]; //lookup all links from the xml file if length of q>0 if (strlen($q) > 0) { $hint=""; for($i=0; $i<($x->length); $i++) { $y=$x->item($i)->getElementsByTagName('title'); $z=$x->item($i)->getElementsByTagName('url');

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if ($y->item(0)->nodeType==1) { //find a link matching the search text if (stristr($y->item(0)->childNodes->item(0)->nodeValue,$q)) { if ($hint=="") { $hint="" . $y->item(0)->childNodes->item(0)->nodeValue . ""; } else { $hint=$hint . "
" . $y->item(0)->childNodes->item(0)->nodeValue . ""; } } } } } // Set output to "no suggestion" if no hint were found // or to the correct values if ($hint == "") { $response="no suggestion"; } else { $response=$hint; } //output the response echo $response; ?> If there is any text sent from the JavaScript (strlen($q) > 0) the following happens: PHP creates an XML DOM object of the "links.xml" file All "title" elements (nodetypes = 1) are looped through to find a name matching the one sent from the JavaScript The link containing the correct title is found and set as the "$response" variable. If more than one match is found, all matches are added to the variable If no matches are found the $response variable is set to "no suggestion" The $result variable is output and sent to the "livesearch" placeholder PHP and AJAX RSS Reader An RSS Reader is used to read RSS Feeds RSS allows fast browsing for news and updates

AJAX RSS Reader In the AJAX example below we will demonstrate an RSS reader where the content from the RSS is loaded into the webpage without refreshing. Select an RSS News Feed in the Box Below Top of Form Select an RSS-Feed: Bottom of Form RSS Feed will be listed here. This example consists of three pages:

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a simple HTML form a JavaScript a PHP page. The HTML Form This is the HTML page. It contains a simple HTML form and a link to a JavaScript: <script type="text/javascript" src="getrss.js">

Select an RSS-Feed: <select onchange="showRSS(this.value)"> Google News MSNBC News

RSS Feed will be listed here.

Example Explained - The HTML Form As you can see, the HTML page above contains a simple HTML form with a drop-down box. The form works like this: An event is triggered when the user selects an option in the drop down box When the event is triggered, a function called showRSS() is executed. Below the form is a

called "rssOutput". This is used as a placeholder for the return data of the showRSS() function. The JavaScript The JavaScript code is stored in "getrss.js" and linked to the HTML document: var xmlHttp; function showRSS(str) { xmlHttp=GetXmlHttpObject(); if (xmlHttp==null) { alert ("Browser does not support HTTP Request"); return; } var url="getrss.php"; url=url+"?q="+str; url=url+"&sid="+Math.random(); xmlHttp.onreadystatechange=stateChanged; xmlHttp.open("GET",url,true); xmlHttp.send(null); } function stateChanged() { if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") { document.getElementById("rssOutput") .innerHTML=xmlHttp.responseText; } } function GetXmlHttpObject() { var xmlHttp=null; try

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{ // Firefox, Opera 8.0+, Safari xmlHttp=new XMLHttpRequest(); } catch (e) { // Internet Explorer try { xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); } } return xmlHttp; } Example Explained The stateChanged() and GetXmlHttpObject functions are the same as in the PHP AJAX Suggest chapter. The showRSS() Function Every time an option is selected in the input field this function executes the following: Defines the url (filename) to send to the server Adds a parameter (q) to the url with the selected option from the drop down box Adds a random number to prevent the server from using a cached file Calls on the GetXmlHttpObject function to create an XMLHTTP object, and tells the object to execute a function called stateChanged when a change is triggered Opens the XMLHTTP object with the given url. Sends an HTTP request to the server The PHP Page The server page called by the JavaScript code is a PHP file called "getrss.php": load($xml); //get elements from "" $channel=$xmlDoc->getElementsByTagName('channel')->item(0); $channel_title = $channel->getElementsByTagName('title') ->item(0)->childNodes->item(0)->nodeValue; $channel_link = $channel->getElementsByTagName('link') ->item(0)->childNodes->item(0)->nodeValue; $channel_desc = $channel->getElementsByTagName('description') ->item(0)->childNodes->item(0)->nodeValue; //output elements from "" echo("

" . $channel_title . ""); echo("
"); echo($channel_desc . "

"); //get and output "" elements

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$x=$xmlDoc->getElementsByTagName('item'); for ($i=0; $i<=2; $i++) { $item_title=$x->item($i)->getElementsByTagName('title') ->item(0)->childNodes->item(0)->nodeValue; $item_link=$x->item($i)->getElementsByTagName('link') ->item(0)->childNodes->item(0)->nodeValue; $item_desc=$x->item($i)->getElementsByTagName('description') ->item(0)->childNodes->item(0)->nodeValue; echo ("

" . $item_title . ""); echo ("
"); echo ($item_desc . "

"); } ?> Example Explained - The PHP Page When an option is sent from the JavaScript the following happens: PHP finds out which RSS feed was selected An XML DOM object is created for the selected RSS feed The elements from the RSS channel are found and outputted The three first elements from the RSS items are looped through and outputted PHP and AJAX Poll AJAX Suggest In the AJAX example below we will demonstrate a poll where the web page can get the result without reloading. Do you like PHP and AJAX so far? Top of Form Yes: No: Bottom of Form This example consists of four pages: a simple HTML form a JavaScript a PHP page a text file to store the results The HTML Form This is the HTML page. It contains a simple HTML form and a link to a JavaScript: <script src="poll.js">

Do you like PHP and AJAX so far?

Yes:
No:

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Example Explained - The HTML Form As you can see, the HTML page above contains a simple HTML form inside a "

" with two radio buttons. The form works like this: An event is triggered when the user selects the "yes" or "no" option When the event is triggered, a function called getVote() is executed. Around the form is a

called "poll". When the data is returned from the getVote() function, the return data will replace the form. The Text File The text file (poll_result.txt) is where we store the data from the poll. It is stored like this: 0||0 The first number represents the "Yes" votes, the second number represents the "No" votes. Note: Remember to allow your web server to edit the text file. Do NOT give everyone access, just the web server (PHP). The JavaScript The JavaScript code is stored in "poll.js" and linked to in the HTML document: var xmlHttp; function getVote(int) { xmlHttp=GetXmlHttpObject(); if (xmlHttp==null) { alert ("Browser does not support HTTP Request"); return; } var url="poll_vote.php"; url=url+"?vote="+int; url=url+"&sid="+Math.random(); xmlHttp.onreadystatechange=stateChanged; xmlHttp.open("GET",url,true); xmlHttp.send(null); } function stateChanged() { if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") { document.getElementById("poll"). innerHTML=xmlHttp.responseText; } } function GetXmlHttpObject() { var objXMLHttp=null; if (window.XMLHttpRequest) { objXMLHttp=new XMLHttpRequest(); } else if (window.ActiveXObject) { objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP"); } return objXMLHttp; } Example Explained The stateChanged() and GetXmlHttpObject functions are the same as in the PHP AJAX Suggest chapter. The getVote() Function

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This function executes when "yes" or "no" is selected in the HTML form. Defines the url (filename) to send to the server Adds a parameter (vote) to the url with the content of the input field Adds a random number to prevent the server from using a cached file Calls on the GetXmlHttpObject function to create an XMLHTTP object, and tells the object to execute a function called stateChanged when a change is triggered Opens the XMLHTTP object with the given url. Sends an HTTP request to the server The PHP Page The server page called by the JavaScript code is a simple PHP file called "poll_vote.php".

Result:

Yes:	%
No:	%

The selected value is sent from the JavaScript and the following happens: 1. Get the content of the "poll_result.txt" file 2. Put the content of the file in variables and add one to the selected variable 3. Write the result to the "poll_result.txt" file 4. Output a graphical representation of the poll result

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By: DataIntegratedEntity Source: http://w3schools.com/php/php_intro.asp

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